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93 GTP with DOHC 3.4L

JWDT2188

New member
So being that this is my first post, hello to everyone, nice forum so far just from the surfing I did earlier, tons of smart folks around here. So I guess I'll start with the obvious things I've noticed and need help with. Bought the car a few days ago out of.... well pure want mostly. Look under it, saw a good amount of oil all over, assumed it was the rear valve cover gasket or something, but after some reading I'm susupecting it less and less. The car does overheat slightly, hasn't touched the red mark yet but it's come close, wondering what the best procedure or starting point would be to cure that issue... uhhh and when I come to a stop.. whether I'm in Drive, or 1st, the idle almost always fluctuates and nearly stalls the motor, not yet though... My priorities for the moment would be the above, oil leaks and overheating are cruddy problems to deal with.. But also, it shift friggin weird, when shifting manually, the car lags badly through the switch, and if I boot it while in drive, I have to let off the pedal for it to shift, or the revs run far too high for my liking. I realize that this is most likely lack of maintenance since the tranny fluid does look somewhat.. yellowish... but from anyone else's experience does this indicate any major issues, or perhaps simple fixes? Thanks for your replies in advance, sure could use the advice, I can do the work, just need to know where to start with this laundry list of issues, and again, I didn't buy this car because I'm daft, I've honestly always wanted one, since driving my friend's 93 GTP in high school.... Thanks fellas.
 


Come on you guys, don't shy away just cause I'm new, I intend to fix any issue with this car, just need some advice since... from what I've heard, these cars are immensely difficult to work on and there are tons of tricks and tips to making things lighter where cost and headaches are concerned.
 
Give it time someone will respoond to your post. Dunno what time it is where u are but its 3:30am here so i doubt many ppl are online. I would love to help you out with your issues but I know nothing about the 3.4 DOHC
 
Much appreciated bud, I'm in western Canada, 12:51 am here. And from what I've read so far, they seem to be horrid to work on but.... I drove it last night and as crappy as it's running now, which is by my estimation... at 45-50% of it's potential.... I was able to wax a BMW, not sure of the model but it was new, and a 400 Pontiac Trans Am, not sure what year, but it sounded healthy. This was on the highway, off the line, the car hasnt much balls really... which is what leads me to these questions... my experience in mechanics isn't in these types of cars, haven't gotten into re-building alot of computerized, sensor ridden, quad cam 6 cylinder cars yet lol. I've only ever owned N/A V8's until now, all of which were built and tuned, but this car, it's something new to me.

Oh and! What is this "knock sensor" as I read somewhere here? Because in park I have a rev limit near 4k rpm, haven't tried in neutral and I dont care to as of yet... what I dont get is, does the 4k rev limit mean that there's a faulty cylinder?? or is it just detecting an ignition issue or something... not really read up on sensors yet...
 
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The rev limiter is so you dont blow up your motor my 93 3.1 had it and so does my 05, nothing to worry about. When I had my 93 I thought it was fubar also cause it would hit 4k and die. Not sure if you have a knock sensor in that car, basically the knock sensor retards timing when pre detintation occurs so your car wont blow a piston. You shouldnt have to worry about a knock sensor unless your car is running hot or your modded. Someone correct me if im worng.
 
Well it does run hot atm but then again the coolant flush most recently done wasn't by me, so I'm not sure of whether it was done properly, dunno what to think yet really lol... And it doesnt knock, it hardly ticks and it has 276,000kms on it according to the odometer. Just wondering if that knock sensor limiting the rpm is an indication of something bad, or if it's just bummed out and needs replacing... cause the car revs very nicely when you give it the beans, and revs to 7k cleanly so far, havent taken it any higher yet. And also, with the overheating, it's worst while idling or while in stop and go traffic, if the fan cuts in, it sorts it out quick enough but I just dont see why it runs that hot to begin with, approximately 120-130 degrees...? And just to be clear, this is the LQ1, 1993, quad cam.
 


Few things I would check with the overheating would be coolant lvls/condition. Check for air in the system and if all that looks ok replace the thermostat. Check for vacuum leaks, plugs and wires for the rough idle. In my 93 I had a horrible Idle and it turned out to be a vacum line that I had knocked loose while servicing. But if this is a new purchase deffinatly check your plugs and wires.
 
Haha funny you should mention vacuum lines, the previous owner said he replaced a few, perhaps he messed something up? I'll try the coolant flush, using the bleeders, and I'll look up the procedure in Mitchell when I'm at work next time so I get the bleeding procedure right... apparently it's quite the process. Any ideas about the oil leak...? It seems to be coming from the rear of the motor... valve cover maybe?? And the idle is so much rough, it just fluctuates and sort of bogs I guess would be the term, typically when rolling to a stop, around 20-15 km/hr downward, seems worse under heavy braking, nearly stalls, most of the time when sitting still it's when the fan cuts in, which is worrying :S
 
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Alright so I guess what I'll end up doing is.. solve the oil leak, flush the coolant system properly, as the previous owner didnt seem up to it, thing just runs far too hot for my liking. And then I'll try tracing all the vaccum lines and then inspect them all, because there's an evident vaccum leak somewhere... umm also, can anyone tell me what optimum running temp would be for one of these cars? Just need it as reference for when I flush the system.
 
i think the stock thermostat opens at 195 degrees, but it might read about 210. at least thats what it does for my car :P
 


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