93 Plymouth laser rs where does this wire go?

[DannyE]

Hi all, I'm new to this forum and kind of new to DSM but since a kid I have always wanted a 1g but life kind of got in the way. I recently picked up a 93 Plymouth laser rs turbo fwd with very low mileage at 80k. I bought the car as a project car at $500 and along with that comes some issues that I have to iron out, the first is the transmission that leaks fluids and has reverse sometimes and the other is well wiring. Now the car does run but I have no clue how seeing he has no upstream o2 hooked up and he did not set the idle correctly by grounding the timing plug and ecu. The car idles at about 2k even when warm and there is this green wire coming from the main harness that everytime it bumps a ground such as the intake manifold, it makes the engine fluctuate up and down? I will try and post a picture of this green wire along with pics of the turbo because the guy I bought it from said it was upgraded and from what I gathered it is because it's an TD05H and I think the car came with a 13g I do believe? any and all help would be greatly appreciated and thanks in advance.

 

[DannyE]

Here are some other pics which I need help with where this stuff goes? I do believe the 4pin connector goes to the upstream o2 sensor that is unplugged because he has a 2pin o2 sensor in there. The vacuum lines I have tried to track down but to no avail. The vacuum line behind the intake is black with red intermediate stripes.

 

[Vegas Smith]

That green wire most likely connects to the idle position switch and that is the prong sticking up vertically on the throttle body. Just add a female connector at the end of the wire and connect it to the switch. Be sure to adjust the switch correctly by doing a quick google search. I'm not sure about your o2 sensor. There should only be one o2 sensor on the o2 housing on an almost-stock 1G DSM.

 

[DannyE]

Thank you bud, I will check that out tomorrow. I will post a picture of the o2 sensor housing and o2 sensor. He has a two pin o2 sensor in there not even hooked up! I do believe it takes a four pin o2 from what I've seen, I will be getting one within the next day or two. The picture I posted above of that four pin connector that is located right below the thermostat I think is for the o2 sensor. I also know that the ICS is no good as well thanks to following the how to on here. Now when I adjust the idle I noticed the link says manual cars, wouldn't the same procedure work on an auto as well? again thanks for all of the help.

 

[Vegas Smith]

Yeah grab yourself the correct o2 sensor and plug that baby in. That sucks that the isc is bad. I happen to have went through all this last month and have an extra good isc I can ship to you for a small amount. Let me know. This all should be the same regardless of manual/auto. Really work hard to fix any boost leaks because these cars are very old and need a lot of new gaskets and seals for them to run properly.

 

[90laserRSfwd]

Get yourself a copy of the factory service manual. A boost leak tester and a multimeter are going to be your best friends when it comes to 1g's (and 2g's).

 

[DannyE]

Oh yeah I know. I have all of the things you mentioned above, the first thing I do when I get a new car is a service manual. I am a cycle tech so the right tools come second nature to me you fellows are right about the boost leaks because when I ran a leak down of the system there wasn't one rubber hose that wasn't leaking. @ Vegas smith, I ordered one from RA for $70 plus shipping, it was an airtex I do believe but having a second isn't a bad idea seeing these new one's are not factory, is it a used one? and how much do you want. When I tried to find a used one at my local wrecking yard they didn't have one, they had one for a 97 eclipse but I wasn't sure it would work so I didn't take the risk. The car is surprisingly straight with absolutely no rust think God because my 88 Camaro track car was riddled with it around the rear wheel wells.

 

[DannyE]

Wow you guys are going to laugh at this. I was going over some pictures i took of the throttle body and noticed that the idle switch isn't even there? well I guess I know where that green wire goes and why my idle is at 2k. Do you guys know where I could find that switch or exactly what it's called so when I go to find one it's easier. Thanks again fellow's for all of the help, I really do appreciate it.

Here is a picture, let me know if this is where the switch goes.

 

[mitsubishikid]

Here is a picture, let me know if this is where the switch goes.

Yes the idle switch is threaded into that hole, you can find one at a wrecking yard, all 90-94 1g dsms with the 2.0 4G63 motor should have them, even the non turbo ones, or you can contact one of the used parts vendors on here, also some early "90s Hyundai Elantra/Sonatas with the Mitsubishi sourced dohc motors.

 

[DannyE]

@mitsubishikid Thanks bud, I will try used first and if that doesn't work I will pick up a new one. I found some new ones at mitsubishi retailers but they $102 WOW. Thanks again guys.

 

[Vegas Smith]

If you cant find one then let me know. Man, why would somebody take that out? I bet it got severely damaged and somebody just did away with it.

 

[DannyE]

Yeah, the guy I got the car from really had no idea what was going on with it. He wanted $1000 for it but I told him there is no way and I would only give him $500 so he took it. As of right now I've cleaned the engine bay and interior up, re seated a tire that was leaking at the bead and I'm fixing all leaks and replacing the belts which make a loud whining noise when started. I also have to remove the transmission because whoever he got to rebuild it must of been not right in the head or something, It's leaking fluid out of the CV area and reverse is very soft when you select it and you have to give it a bit of gas to engage it. It shifts through all gears fine but like I said, it leaks and reverse is sketchy at best. Do you have that throttle body switch? if so how much would it take to nic it off you? oh and the IAC. Thanks again fellow's.

 

[DannyE]

OK I have an update, I was looking around the transmission today and you will never guess what I found? I found the idle switch just laying there on top of the transmission. Well I installed it and then grounded the ecu and timing pin to adjust the biss. I started the car and started to adjust the biss but no matter where I turned the screw the idle never changed? it remained at 2k rpm :O well the I disconnected the grounds and the idle dropped to about 1400 rpm and remained steady but after about two minutes it started idle up and down from 1500 to 2000 rpm again. Also when the switch is unplugged the idle stay's steady at 2k rpm but as soon as I plug in the idle switch it starts to idle up and down again, it does the same thing if I take the connector to the idle switch and touch it to a ground. I know I need the ISC and o2 sensor and I also know I shouldn't be starting it without them but I wanted to see if that switch would fix the high idle and it didn't. I'm going to go ahead and get that o2 sensor and wait until that ISC comes in and re try to see if this gets any better. I will make sure to keep you all updated as I do things so you know where I'm at, if I have to take a video of it I can do that so it gives you guys a better perspective of what it sounds like.

 

[Vegas Smith]

Getting the idle setup on these cars can be very hard. Check and make sure your throttle cable isn't too tight. Disconnect it from the throttle so that it sits loose and see if that helps. Calibrate your tps sensor as well as both the tps and throttle cable directly alter your idle. Check for airleaks at the biss screw, throttle body seals and the isc gasket because any of those can cause the idle surge you are referring to.

 

[mitsubishikid]

Not having an ISC [or a bad one] can cause the up down idle, I recommend that you don't idle the car until you have all the right sensors back on it, a bad isc can blow out the ecu's ISC drivers... so you might want to inspect your ecu too, just to stay on the safe side.

I would definitely say you need to do a boost leak test too, you can buy the tool on ebay, or make one like I did they are worth every penny IMHO.

Also while your waiting on parts, I'd recommend that you clean out your intercooler, I like to seal both ends of the cooler with a few disposable gloves, and then pour some gasoline inside, then shake it around and pour it out into a suitable container, repeating the process [with fresh gasoline] until it comes out looking clean.

 

[DannyE]

OK guys, I will do all of the above. I agree about not idling the car until I have all of the sensor's. I have a boost leak test and when I tested it two of the hoses were leaking so I have to replace those. Thanks again fellas for all of the help, I will make sure to report back as soon as I get all of it done.

 

[DannyE]

Alright, I got the car idling perfect following all of the info I gathered from this site and others. I changed the oil and drained the gas tank and added fresh 94 octane, I let the car warm up and blipped the throttle a few times. I then turned the car off and let it cool and re started it, well while idling the car cut off on me? well I go and check all of the fuses and they were all good then I removed the timing belt cover and yep you guessed it, a snapped timing belt :O so i went ahead and removed the cams and the spark plugs then covered the spark plug tunnels with my hand and it appears cylinder 1 and 4 have no compression while cylinder 2 and 3 have a little pressure. I guess this goes to show when in doubt just change the damn timing belt. I suppose from here I remove the head to see the extent of the damage, at the least I know it's going to cost 220 for the timing belt kit and probably 400 to 500 for the cylinder head. Plus it's winter and I do not have a garage so I can only work on it when it's decent outside . Do you guys know of any machine shops around the Winchester VA area that is competent enough to do 4g63 cylinder head work? Thanks again for all of the help guys.