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Resolved New build ran for a day, now won't start

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sypherzero

15+ Year Contributor
461
7
Feb 14, 2008
Marion, North_Carolina
Okay guys, I'm starting to become even more confused. I recently finished my build and got it installed into the car. Two Fridays ago I started the car for the first time, it started right up, idled a little high but then came down to around 900 RPM. I let the car get up to temperature then took it out for a drive. It didn't miss a beat! The motor felt strong, temps were good, oil pressure was good, just a really small oil leak and nothing else was wrong.

We drove the car around 4.5 miles then had to park it because it was late and I had to work the next morning. I even started it up again before we left it and moved it over a couple of feet from where it was originally parked. After that the car sat over the weekend until I tried to start it Monday evening. The car started right up, had a slightly rough idle, but nothing crazy, so I figured I'd put a few more miles on it. Nope. I started out of the drive way and went to go up a hill and the car felt like it had no power, it struggled to get to the top of the hill. As I was turning it around to head back home, it kept dying.

Now, if you can get it to idle, it's misfiring and only idling around 1-200 RPM. Once in a while if you press the gas pedal repeatedly, then hold it all the way open, you can get the car to roughly 2000 RPM, but once you let off it dies again...

So at this point, I've drained the gas tank twice, it has it's 2nd round of 93 octane in it. I've tried 2 different MAFs, 2 different coil packs, and 2 different throttle position sensors. It's getting spark on all cylinders, you can hear the plug wires arch to the plug walls if you remove them with the car idling. Compression is good (180, 180, 175, 180), and timing is spot on. You can tell that it is getting fuel too, because you can smell the un-burnt fuel in the exhaust gas.

The motor is an Evo I-III block, stock 2G pistons and rods, ACL Race main and rod bearings, new Nippon rings, crank was polished, all new Fel-Pro gaskets and seals, stock 2G cams with stainless valves and BC springs and titanium retainers, OEM BS eliminator parts, timing belt, timing tensioner, idler pulley, and tensioner pulley.

All of the sensors/solenoids are plugged up, but there isn't any coolant running to the throttle body (looped back to coolant pipe), no vacuum lines running to boost solenoid, or either of the emissions solenoids. The ECU is a socketed 95 Eprom with a relatively stock tune from My1GDSM.

Where else should I look? I'm so damn stumped right now. No, I haven't done a boost leak test, but all couplers and clamps are tight. Crank sensor? Cam sensor? Any help is greatly appreciated.
 
I had almost the same thing happen to me, test drove after installing built motor, then the next day would barely start, then wouldn't start at all. I was able to pull a CAS code. We had put my stock 2ga cams on it and the 2ga CAS just crapped out. Switched to a 1g CAS and problem fixed.
 
I had almost the same thing happen to me, test drove after installing built motor, then the next day would barely start, then wouldn't start at all. I was able to pull a CAS code. We had put my stock 2ga cams on it and the 2ga CAS just crapped out. Switched to a 1g CAS and problem fixed.

I'll try and check the code tomorrow and see what it is.

Do you have a log we can look at?

I don't. I just have a socketed ECU with a burned/flashed chip from My1GDSM.
 
First, your profile needs to be updated with a complete mod list.

What injectors are you running?
What fuel pump?
Do you have a AFPR? If so, what's your base fuel pressure?
Did you sent the base timing after the build?
SD on a chip? Really?

You should probably think about investing in some tuning software. Chips are great for cars with simple bolt-ons, but a build like yours is going to require tweaking over time, especially on SD. You're also going to have a hard time troubleshooting without a way to see what the car's ECU is actually doing.

If you plan on sticking with the chip, you should hit up the guy who burned it and see if he can assist you with some of your troubleshooting.

Think about it: You're saying the car is mechanically sound (compression and timing) and you have fuel, spark, and air...That would indicate to me the system(s) tying all of those things together aren't functioning properly for whatever reason.
 
First, your profile needs to be updated with a complete mod list.

What injectors are you running?
What fuel pump?
Do you have a AFPR? If so, what's your base fuel pressure?
Did you sent the base timing after the build?
SD on a chip? Really?

You should probably think about investing in some tuning software. Chips are great for cars with simple bolt-ons, but a build like yours is going to require tweaking over time, especially on SD. You're also going to have a hard time troubleshooting without a way to see what the car's ECU is actually doing.

If you plan on sticking with the chip, you should hit up the guy who burned it and see if he can assist you with some of your troubleshooting.

Think about it: You're saying the car is mechanically sound (compression and timing) and you have fuel, spark, and air...That would indicate to me the system(s) tying all of those things together aren't functioning properly for whatever reason.

You make some very good points, and I thank you for your input. However, I don't know where you read that I am running Speed Density? I stated that I switched out two different MAFs. As long as everything holds up over time, I will definitely be upgrading the car to ECM Link. And I will get in touch with Stacy at My1GDSM to see if he can be of any assistance. Also, I'll update my mod list momentarily.

I continued to do some more research on here, and it almost seems as if my problem may be linked to a faulty coolant temperature sensor or maybe a bad sensor ground on the ECU? Do either of those sound like the culprit to you?
 
In my experience a faulty CTS will cause rough start up but runs fine once warmed up.
Did you drive this car before the build? If so, how was it running? Also, is this motor freshly built, or did you get it used? What cams and CAS are on it? There's so many different variables here. How's the alternator and battery? Are the lights/radio shutting off when it dies? IAC? You must do a boost leak test! Tight clamps don't mean anything as I've learned the hard way.
As I'm sure you know, there's various tutorials on testing the CTS, IAC, CAS, etc. I was able to narrow my problem down to the CAS and happened to have a 1g on hand (which you should upgrade to anyway if you have the 2ga), ironically I was only able to pull the code after I tried and replaced 10 other things. Also it goes without saying to double and triple check all the plug connections on the harness. Keep at it, you'll figure it out.
 
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However, I don't know where you read that I am running Speed Density?

Sorry, saw it on your wish list. I misread.

A faulty CTS could absolutely cause a no-start.
 
Had something similar happen to me, car would start and run fine but when I turned it off it would take about 5 times starting and dying to get it running and even then it ran like crap. Had to start it and floor the gas and it would get to 2k RPMs and die. Turned out to be the case was 180 out. Might not be your problem but easy thing to check.
 
I was able to test out a few more things during my days off this week. We checked the CTS, CAS, and CPS, and they all checked out. I pulled the ECU and opened it up. There are a few spots on there that concern me. I've looked at other threads that show leaking capacitors, but mine doesn't look quite like any of those. Here are a couple pictures of the areas that concern me, maybe you guys can take a look at them and tell me what you think.

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Just heard back from Steve, he doesn't think those spots on the ECU are anything to worry about. I'm running out of things to test, and I'm honestly getting tired of getting nowhere with the car. If I can't make any progress, I'll have to let it go.
 
Keep at it man. I had similar frustrations on my most recent purchase. Turned out just to be the fuel filter needed changing. A silly maintenance thing, but it had me going on circles for weeks.
 
Keep at it man. I had similar frustrations on my most recent purchase. Turned out just to be the fuel filter needed changing. A silly maintenance thing, but it had me going on circles for weeks.

I'll definitely keep at it. Providing the weather holds out, I'll test the fuel system on Friday. Hopefully it is something simple like the fuel filter.

Lets see the rest of the ECU board. You were wondering about a blown sensor ground.

Here is the rest of the board. After doing a little more research, I don't think it's a blown sensor ground, but I could be wrong.

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Correct, the sensor ground is intact.

I don't remember, do you have something to log and read DTCs from the ECU with?

No sir, I don't have any way to read codes or anything to log with.


I'm planning on testing the fuel system on Friday. I've been doing some research, but I can't find any definite answer how to test pressure at the rail. Can anyone walk me through this? Is there a kit I can rent from one of the local auto parts stores?
 
Yes, you can rent a fuel pressure test kit. Harbor freight has a kit as well for 25 bucks or so. Not a bad investment.

Fuel can be tricky so doing it the right way is important. When I had my issues I saw fuel on the plugs when I pulled them and ruled out fuel issues. Shouldn't have prematurely ruled it out as a problem.

I'll let smarter people then I chime in on best practices for the procedure.
 
It ran again! I pulled off the fuel rail to visually verify that all of the injectors were firing, and to see their spray patterns, and found some sediment type stuff in the rail. And a note to anyone who is planning trying it, I would not recommend it to anyone else. I've read a few different threads where some members say it won't pop injectors off of the rail, but mine did, and I have brand new seals on them. So I pulled everything off, cleaned it out and decided that I would test the FPR. After putting some compressed air through it, it sort of sounded like a duck call. This led me to believe that perhaps the diaphragm in the FPR was damaged. I had another one lying so I figured I would switch them out.

After priming the pump, and several key turns later, it started and idled on it's own! After letting it get up to temp and revving it for a little while, I took it up the road again. Now it feels as if the car is struggling to get enough fuel to sustain anything over 2500 RPM, it almost feels like fuel cut, but it can't be. So now I'm thinking that the fuel sock/strainer is pretty well clogged, and I'm sure the filter isn't in any better condition, so I'll plan on getting those switched out with new parts in the next few days.

Thank you all for your input and insight on my situation. I'll keep this updated once I change out the fuel filter strainer and fuel filter to see if any more problems pop up.
 
Another update on the situation, it turns out that the gas tank itself is rusted to hell. Rust particles/sediment were making their way through the strainer, pump, and filter all the way to the fuel rail and clogged all of the injectors. Removed everything again today, replaced the tank and filter with one from MIP, new strainer/sock and new fuel filter. Got the majority of everything put back together today, just have to tighten a couple things and attach a hose or two, add fuel, and it should be back to life.
 
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