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In Need of Second Opinions on Electrical...

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gunnermaiden

Proven Member
72
1
Jul 27, 2016
Phoenix Area, Arizona
First off, apologies for the LONG read in advance.

Secondly, I'm very sorry if some things have already been mentioned in this post, I could not seem to find the clear details and answers I was looking for.

Thirdly, hello everyone!

I have a 99 GS (auto) 420a non turbo that I picked up as a running-project to have it built the way I want. My main goal right now is to restore it and have the proper work done on it to continue keeping it on the road the way it was meant to be. These cars are more and more difficult to find in good, unmolested condition and I want to save this car. Fortunately for me, money isn't a problem but that does NOT mean I am wasteful with my funds, I am a careful spender and rather particular because I used to be poor as fck and I worked hard and long to be where I am now. Moving forward,

The kid who owned it before me destroyed it. Wires every which way, leaking trans, lots and lots of electrical problems, which seems to be most of my problems. Here's a description of the things going wrong that I believe are all electrical related:

-Rough start. Starts everytime, just roughly
-Will not run cold, must wait for it to warm up
-Rough idle -- sometimes bogs down and almost stalls out at stop signs/lights
-Dash is obliterated. The only thing that functions properly is the speedometer. Won't display anything.
-Interior lighting (when the headlights are on) flashes on and off randomly and can't seem to stay on
-A/C is out. Recharged it, blew cold, but then made my PCM(?) overheat and then A/C lost power (being in Phoenix, it's a big deal to not have an A/C)
-Upon driving, trans is unpredictable. Some days it has zero issues, moving through no problem. Other days it won't move into third. I believe this is electrical considering how the rough the wiring is visibly. However, it leaks and I don't know the status of the leak.
-I guess I might as well mention that the doors only open from the inside, no door panel cover on the driver's side, and no radio in it at all. The previous owner removed it since you have to leave the windows down to get in it and it looks like he messed with the wiring behind the radio compartment as well.

There are a lot more issues, although the electric is my main concern right now since I am mostly concentrated with how healthy it runs and not how it looks/how comfortable it is at the moment. The body is straight with no rust (AZ car). It might be at 177xxx original miles, but I don't know how accurate that reading is on the dash considering nothing else on it works properly.

I did drop it off at a garage that specializes in restorations last week. This week I received an email from the owner that said this:

Ac system low on freon, serviced system & ac does blow cold at this time but shuts off do to computer temperature going high. The Gauge on the dash shows normal but when you hook up the computer scanner it show high above 230 but then loses temp & drops below normal and back up. Lights on your dash like the check engine light not coming on, there are several codes that come up on scanner. The starting issue has always started but sometimes not so easy. With all the wires just routed places, I think that the best place to start on this car would be a new wire harness & PCM

So here's what I need a second opinion on. My quote is roughly 10 hours worth of labor to replace and rewire the harness and PCM. Which is going to end up to be around $1k or so (it's stated that is could end up being a bit less in the end). Is there ANYTHING else I need to have replaced for this particular part of the project? Any related related relays /computers other than the PCM? Any fuses? Suggestions to look for to advice the shop on? Owner of the shop has not yet responded to what the codes are saying exactly. I know that 2 off hand already are going to be for the exhaust and the airbag (aftermarket parts installed by previous owner), but I have no clue what the rest could be. Note: I am going out and buying the replacement parts and dropping them off at the garage since I wanted to be the one to pick the parts, which is why I am asking these questions
 
New (used) engine and cab wire harnesses are one of the best things you could do to start your restoration. Otherwise you will spend countless hours tracking down one problem at a time.

Since you like to buy the parts for the shop to install, check with Stephen Miller (Stangmudera) on this forum. He is a sponsoring member and can get you all the DSM parts to restore your ride.

I have to admit, I've never heard of the ecu temp rising due to the A/C, but maybe the 420a's are different in that way.

Welcome to DSMTuners and best of luck with your new ride!
 
Don't waste your money "restoring" a 420a. They are a dime a dozen. If you want a project pick up a car worth working on. I went through several 420s back in the day and after I got my first 4g I couldn't believe how much money and time I seemingly wasted years before. The reward factor just isn't there. 4g63s are so cheap nowadays it's ridiculous. Whether you luck out and find one bone stock, or inherit someone else's mess it's worth it tenfold.
I'm not trying to be a dick but that is the general consensus, especially if you're actually considering paying someone to do the work.
If your dead set on polishing a turd, go to your local junkyard and pull a ecu and harness from a 420a. Most yards across the country are packed with them. Or, contact Stevie and I'm sure he'll hook you up super cheap.
Download a FSM and learn to do it yourself, as the labor costs alone will be astronomical.
Believe me, I completely understand your mindset at this point, but if you take my advice and cut your losses before you won't regret it when your ripping around in a "restored" GST,GSX, or Tsi, Tsi awd.
Either way, welcome to tuners. This will be the place you learn the most about this platform. Stay away from mechanics as much as possible or you'll go broke ( no matter how much you have) as these 20 year old cars require almost daily maintenance.
 
Thanks Sunshine -- I'm sure the OP appreciates you calling his new ride a turd.

We've had several DSMs including 4G63, 4G64, and 420a. While the 4G63 and 4G64s were being rebuilt (again!), the 420a was a great daily that kept singin' along -- while we used it to pick up parts for the other cars.

Gunner, get your 420a fixed and driving. You will learn much about DSMs along the way that apply to all the models. When this one is running well, then pick up a perpetual project car
 
So here's what I need a second opinion on. My quote is roughly 10 hours worth of labor to replace and rewire the harness and PCM. Which is going to end up to be around $1k or so (it's stated that is could end up being a bit less in the end). Is there ANYTHING else I need to have replaced for this particular part of the project? Any related related relays /computers other than the PCM? Any fuses? Suggestions to look for to advice the shop on? Owner of the shop has not yet responded to what the codes are saying exactly. I know that 2 off hand already are going to be for the exhaust and the airbag (aftermarket parts installed by previous owner), but I have no clue what the rest could be. Note: I am going out and buying the replacement parts and dropping them off at the garage since I wanted to be the one to pick the parts, which is why I am asking these questions

every time someone has told me that they took their car to a shop and the shop told them they need a PCM and a harness, it has never needed either. most of the time it is a blown fuse or a bad relay. and never over $30 in parts.

The only times i have ever had to replace a harness on a DSM, is when it was damaged by fire or i was doing some kind of swap/conversion.

Now which harnesses are they replacing? If its just the engine harness and PCM, 10 hrs is way too much. The PCM is in the engine bay, it takes like 1-2 minutes to pull it, max. The engine harness shouldn't take more than a couple hours max.
Shit, with a lift and a helper, swapping the engine and engine harness shouldn't take more than 8hrs.

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if they are also replacing the "B" and "C" harnesses, then 10hrs is about right.

to remove/replace the "C" Harness, the dash has to be unbolted but you don't have to remove the dash from the car, just pick it a few inches.

the "B" harness is kind of a cox sucker cause you have to pull the dash out of the car. Its attached to the metal reinforcement that the dash sits on.
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If it were me, i would much rather just fix the existing wiring than have to pull the dash out to replace the "B" harness.


----------------------
Don't waste your money "restoring" a 420a. 4g63s are so cheap nowadays it's ridiculous.
Believe me, I completely understand your mindset at this point, but if you take my advice and cut your losses before you won't regret it when your ripping around in a "restored" GST,GSX, or Tsi, Tsi awd.
Stay away from mechanics as much as possible or you'll go broke ( no matter how much you have) as these 20 year old cars require almost daily maintenance.

I totally agree. its a waste of money, even more so cause its an Automatic.
 
Tackle your restoration in stages, not full on. I'd recommend getting at least the doors opening properly first. Probably something simple like the rod linkage to the outside handles. Then you can get the panel put on.

Winter is coming. Not sure how much of a winter you get where you're at but you could *probably* hold off on getting that a/c looked at until early spring.

As for wiring harnesses, get the factory service book (there's a download on here) and see what is or isn't working, making a list. (Be sure to check fuses first.). And possibly, troubleshoot those issue separately unless you're dead set on getting a wiring harness.

Rough idle could be caused by many things. Weather, fuel quality, clogged injectors, etc.

Transmission (shivers), where's it leaking from? Axle seals possibly?
 
I guess I should talk about a few things and why I have this car in particular:
I literally couldn't give two turds if it's auto or manual. I like both, drive both, no preference. Both are good for their own reasons and situations. I really will never understand this battle in the car community but then again why bother trying to understand it, especially since I am the one driving it, not you.

Secondly, I can't FIND any other models in my area. I looked for 3 months, I almost grabbed a GSX but ran the VIN and found out it was stolen so no-go there. And the ones I have found are in WAY worse condition than my 420a, even with a trans leak, or they were asking way too much for a car that needed a lot of work. My goal was to find a 2g Eclipse of any model under $1k that ran, drove and could pass smog and this car met that goal for me. I figured being a first time DSM'er that was a good place to start especially considering that I don't have access to a place where I can do repairs myself. (Condo place would fine me heavily if I was caught turning wrenches). I could get away with doing small repairs, switches and quick oil changes but not something of this size. I'm actually planning on doing the interior restoration at my condo, which I'm very excited about starting even though that's a lot further down the road. The other cars I checked out were beyond worse condition than mine around the time I was buying so I think I lucked out. I can still drive it even in it's current condition, and it still passes smog. I figured based on my independent research a 420a would be the best way to start for a n00b DSM'er. I have experience tuning and repairing all-motor Hondas which are obviously much easier and way more manageable. However I do NOT have experience with turbos and I'm not comfortable with maintaining a DSM turbo yet.

Thirdly, I did a bit of research on models before I started my car buying search. I'm happy with my 420a even though it's auto trans N/T because I want a car to build up the way I wanted it to be, something to play around with and customize. Although the process to change things to add more power are a bit longer of a path to make it is possible. I got this model in the because I wanted to learn. I want the base done right the first time which is why I decided it was best to pay someone to help me with the electrical restoration.

So that's why I have 420a and I decided to restore it. I already understand that I will be throwing parts at it often, I figured that's how it would've been with any DSM I picked, but it will definitely help me learn about DSM's like I wanted.

Thank you for your honest opinions anyway and I will still consider all of them.

@DogWhistle , thank you! This car is being rebuilt mainly for the purpose of being "my family is visiting and I don't want something too crazy to scare them in" car. I'm getting a mint S2000 soon and I need another car with at least 4 seats and I picked this car.

@PlanZero , I will take that into consideration the day I pick up a different DSM. But for now, I think this is where I want to start although others may not like it. I don't think this car will waste my money because I'll definitely get what I want most out of it - knowledge and experience. And I know how priceless that is now because I wouldn't be where I am without it.

@dustyboner , Thanks for the diagrams, that's exactly what I needed! But yes, they are replacing all of those harnesses. I dug around through the entire car for about 3 hours or so and trust me, it needs new harnesses. I should have taken pictures but of course I didn't. The previous owner literally cut wires, added new ones to the cut parts using tape, and they lead to nowhere. It's a total hack job, everywhere, I don't even know what they were trying to accomplish. I have to replace the dash anyway (cracked and dysfunctional) so taking that off was also on that agenda. This is also the only time I am taking my car mechanic, I mostly want to do everything I can get away with myself. I killed my last project trying to wire myself, but I also don't have the time to tackle a big wire job anymore as I run a gun store about 60 hours a week, then in my spare time I'm back at the range training. Welding will be about the only other reason other than electrical for me to take it to a shop. I can handle pretty much anything else.

@tunedbysaturnsl , It's a broken rod on the driver's side, I know exactly where it's broken too. Fortunately my hands are small enough to where I can actually get in there and replace it without taking the door apart since the panel is already removed ROFL . I don't have a clue where the trans is leaking from. Didn't notice it until I pulled it into the shop. It is a very small leak if I hadn't noticed it until then, and it didn't seem too wet from the leak. I believe this is a result of the electrical issues, shop owner just got back to me on the codes which makes me think that is true.

Also, shop owner got back to me with codes! Catalytic converter, transmission control system and a lock up code. As I mentioned before, I think the catalytic one is due to the exhaust being aftermarket by the previous owner. I will definitely take in suggestions to any ideas what else it could be. The trans control code explains a lot of it's behaviours. The lock up code, I'm at a loss on that one.

Sorry if I missed anything!
 
my guess on the catalytic converter code is either a bad rear o2 sensor, a gutted/removed cat, or the exhaust did have a bung for the rear o2 and the sensor is zip-tied to the harness.
 
For anyone that's actually still reading this, I am pulling my car out of the shop next week. I didn't end up replacing any of the wiring yet, (still doing independent research not feeling comfortable enough yet) just had them concentrate on the A/C. It officially blows cold air - yay! They added more Freon and supplied adequate power to it (wires were spliced). However - it runs my computer temp high, it overheats, and the A/C powers itself down. Wtf? Bad wires/wiring, dead fuse, bad computer, or not enough power/too much power? Not sure where to look first.
 
computer temp? what computer and how do you know its overheating? are you talking about the A/C compressor control module in the passenger kick panel area?
 
computer temp? what computer and how do you know its overheating? are you talking about the A/C compressor control module in the passenger kick panel area?

...good question, she made it sound like it was the PCM. Shop owner didn't clearly state, guess I'll be asking her when I pick up my car next week.
 
i would check to make sure the compressor clutch relay is still working when the A/C stops. when some relays go bad, they will stop working after they get hot and will work again after they sit for a while.

next i would check to see if the coolant temp sensor is within spec and that the PCM is reading it properly. The compressor will shut down if the coolant temp (what the PCM is reading, a bad sensor or wiring could show a much higher temp than the actual temp) is higher than 226F or 239F, im not sure which one as the manual has both temps listed.

it could also be:
-fin thermo sensor
-dual pressure switch
-revolution pickup sensor (on the compressor)
-compressor control computer

here is the terminal checks for the compressor control computer
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i would also ask the people working on it, what the pressure readings were for the hi side and low side. just because what they are telling doesn't sound right and if they think you know more than you do, they are less likely to try and rip you off.

here is the standard values for the high and low pressure sides:
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If the low pressure side is higher than 32psi or the high side is higher than 370psi, the compressor will turn off.
 
Make sure the ac fan kicks on when you hit the button
The fan has always worked fortunately, when I first picked up the car the fan kicked on but blew warm. Now it blows cold, dies, blows hot again. I might put the A/C on the back burner if I can't get it done the first try this week with cooler temps on the way, I would like to move onto the transmission.

(It slowly leaks, not sure from where yet and it also leaks clean not burning anything, moves through gears 9/10 times and for the 1/10 it doesn't go into third). I think the solenoid is dying based on the creeping/research I've been doing on here, and it threw a lock up solenoid code which further grounds my estimated guess. It's possible there's a short or snipped wire somewhere too. The grounds all looked good when I checked, but I will check again anyway. I think the very first thing I'm going to work on when I pick it up tomorrow is getting the locks to work right, fixing the door handles and replacing the door panels. Also, with the current status of my transmission am I doing any further damage to it by driving it?
 
Wait is this car a GS or GST? Fix your profile for future reference, as these cars have completely different engines, trannies, ecus, etc.
And what actual codes are you throwing? I don't know what a "lock up solenoid" code is. We need numbers.
If I were you I would concentrate on the mechanical issues before I worried about aesthetics. The door handles and ac don't mean jack if the car isnt running. And I meant the ac fan on the radiator, not the blower, just to clarify.
And yes, you will most likely cause more damage by driving it. If you already planned on a new head gasket from overheating, or a transmission rebuild then go ahead and beat the brakes off her. At the most basic level, make sure the tranny fluid is full.
 
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@PlanZero , it's a GS. Plain old base model auto Eclipse, so boring I know LOLz. I don't know what the numbers are, this is just based off of what the shop just informed me. There's some more details in an earlier post I made in this thread about the codes. I'm getting a code reader this week so I will go into more details later. I am picking up my car Tuesday so I can't really do anything right now.

I'm not worried about aesthetics, I would like to be able to lock my car is all since I do not have a garage and I have to park it in a somewhat public parking space. There's nothing in there to steal but that's not the point I don't appreciate people touching my shit regardless and there's no reason to give anyone a reason to take a look and invite themselves in. Security thing, which I do not take lightly, I've had autos stolen from me before so getting it to lock properly is kind of a big deal to me.

I'm not sure where the A/C is having issues, I didn't look a lot into it before I dropped it off. It seemed more of a simple problem since it seemed to be fine other than no cold air so I didn't think much of it but I guess I was only scratching the surface. My main purpose bringing it to the garage was to have it completely rewired but now I want to do more research on that before getting into that process. I have a feeling it's going to need it, but I'd feel better with more knowledge about it first.

To clarify, my car isn't overheating, just the computer "supposedly". Another thing I will have to look into myself. When I checked on the radiator the day I bought it (which was only 3 weeks ago) everything on that end was great. The motor runs fine the most major problem I have is the trans issue and I'm dead set on the idea that it's all electrical/computer related the more I read about these cars. *shrugs*
 
Well i dont believe the ecu is overheating, and no offense, but this shop sounds sketchy to me based on what youve said so far. If that was my GS this is what I'd do when I got it back, in no particular order.
1) get a cheap code reader ($20) or at least take it to autozone and have them print them out
2)replace gauge cluster (junkyard or eBay for less than $50)
3) check your tps (throttle position sensor); even on the non adjustable 420a tps it can cause all kinds of auto tranny problems- 3 auto dsms I've owned all had "transmission" problems- hard shifts, missed shifts, shuddering downshifts, all wound up being tps.
4) test/ replace coolant temp sensor ($20 and 10 minutes to replace); I've noticed on 420a motors the bad CTS causes starting issues and cooling issues, as the fan is tied into the CTS
5)possibly replace ecu
6) Check your tranny fluid. Make sure it's red and stinky. If it's burnt, change it. If you're leaking fluid you must top it off or you'll destroy your tranny. Find the leak. It's probably an axle seal, but you may luck out and only be a cooling line. It's not a coincidence that you have a leak and tranny problems.
These parts (for a 420a)are very cheap, especially used. If you have a junkyard nearby you'll find them. If not, contact Steve Miller. The repairs are very easy and can be done with simple hand tools in a parking lot.
 
@PlanZero , your plan sounds WAY more manageable, definitely going to start with your tips when I get it back tomorrow. I have to get a new entire dash anyway since it cracked and faded from the AZ heat. I'm thinking now that you mentioned all of these, I don't need to rewire the cab harness. There's three junkyards are that are pick-and-pull style I'll start there since I want to avoid shipping costs as much as possible.

I also may be getting access to my own on-site garage this month which is allow me to do even more work at home, obviously!
 
Picked it up today, on the way home it wouldn't go into third again. But I have codes: P0420, P0700 AND P1775.

Here's what my invoice says: A/C low on Freon, vac and charged A/C to factory specs. A/C works but computer says temp 228-239 and will shut off A/C compressor. Wiring issues, gauges don't work, trans fluid leak, hard start may be due to fuel injector leaking down. Recommend to start off with new wiring harness and PCM.

Okay so I turned the A/C on for 30 seconds and it blew cold. Turned it off for 20 min while I drove, turned it back on when I parked, blew hot. After what PlanZero stated in their last post, I'm going to disregard the hard start up due to the "fuel injector leaking down", I don't even know what that means. First thing I'm going to do is replace the TPS since that seems to be the most logical thing to start with my trans and not to mention an easy job.

They left no other information for me and were gray about any other questions I asked, not helpful. Deff the last time I go to a shop unless it's for welding, as stated before. I also have a basic pic of my engine bay, so you can see what a mess it is and how much work I have to do.

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Sorry for not getting out further with the close up, I'm not very tall >.>

Ah yes and before I forget, just checked the trans fluid level, it's good so it must be a sloooooow leak because I haven't added any since I bought it 3 weeks ago now.

Still need to get underneath the car to locate the trans leak, hopefully I'll have my garage access soon...
 
P0420- rear o2 sensor- if the cat was removed the rear o2 is not reading properly. Assuming you still have the rear 02, get a $5 02 sensor spacer off eBay which extends the sensor out a bit to fool the ecu (either way, it won't affect performance)
P0700- trans fault detected
P1775- I'm not 100% sure but I believe it's a Chrysler trans code.
Check the condition of the TCU (on a 4g it's behind the console/ radio, not sure on a 420a. You may want to take it to a tranny shop to read the trans codes. You may luck out and it only be a faulty TCU.

Make sure you check the trans fluid properly. After the car is running for a while, keep it running, shift through the gears and check in neutral with the ebrake on, while car is running. Should be in the HOT zone

I'm not at home so I don't have the FSM in front of me, I'm just going by google
 
@PlanZero , P1775 is a Chrysler code, I guess it depends what it means depending on what car it's on. But either way it is a trans related code.

I also found this lovely article on here (it's for a turbo 420 but a lot of things are in the same area): http://www.dsmtuners.com/threads/2g-engine-bay-electrical-connections.298047/page-2#post-151542278

which shows me that the previous owner of my car removed the CTS. I'm still skimming the article and there's not a lot I know yet about my bay quite yet, I'm sure I'll find a lot more missing things though. Probably going to print that out and keep a copy of it in my car, and make a list of the things I need.
 
Snowboarder's helpful thread is for a 4g63, not a turboed 420a. Completely different bay, all Mitsubishi. Your car is all Chrysler. Although the CTS is in roughly the same spot on the tstat housing. It's the larger of the two sensors. The smaller one above it is for the dummy gauge on the dash.
 
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