ManicMechanic Posted October 2, 2008 Report Posted October 2, 2008 Ever since the car lost it's coolant last and I fixed it, it's been running like crap at idle. I've checked the compression and all 6 cylinders are within spec. I've checked the injectors and all 6 are within spec. The plugs are firing correctly. Plugs, wires, ICM, ECM, PCV hoses, PCV valve and coils are new. IAC was gummed up and didn't move at all. I sprayed the hell out of it and got it unstuck. No change. I put a good junkyard IAC on it and still no change. No vacuum leaks, I sprayed carb cleaner everywhere and only made a mess. No loss of coolant what so ever. Timing belt is good and the cams are in time. Runs fine when cold and over 2000 RPMs. When it gets warm, it misses and bucks at idle. It has a random miss that I just can't track down. I had the vacuum line off the FPR and that made no difference. Throw ideas at me. This is a 1994 3.4 DOHC. Quote
oldscsc Posted October 2, 2008 Report Posted October 2, 2008 Clogged throttle body? I don't know why it'd be doing it intermittently, just giving you ideas. In the 'Burb (not quite the same vehicle ) it misses pretty badly, especially on humid days. After looking at everything pretty closely, there was a hole in the distributor When it rained or was humid, the spark wasn't getting where it was supposed to be before it was extinguished. Quote
ManicMechanic Posted October 2, 2008 Author Report Posted October 2, 2008 O2 sensor? Replaced that. And there are no codes. The car passed emissions with flying colors as well. Quote
ismellrealbad Posted October 3, 2008 Report Posted October 3, 2008 cts? maybe running on low coolant fubared it Quote
95 vert Posted October 3, 2008 Report Posted October 3, 2008 EGR stuck open? Proper vacuum to MAP/ MAF hose sealed good? Quote
Cam'ron Posted October 3, 2008 Report Posted October 3, 2008 Throw ideas at me. This is a 1994 3.4 DOHC. Thurs yer problem... j/k that does seem very odd dude, hope you get it straightened out Quote
1990lumina Posted October 3, 2008 Report Posted October 3, 2008 On my 3.1 when I had the idle issue when warm - my plenum gaskets were elaking - even after I sprayed carb cleaner on everything more than one time. Hell I sprayed every inch of those gaskets like 10 seperate times - I ended up removing the plenum to replace the fuel injectors - replaced the gaskets and bam, everything is okay. Quote
ManicMechanic Posted October 5, 2008 Author Report Posted October 5, 2008 I sprayed carb cleaner around the EGR valve today and it died...I think I am on to something there. New gaskets ordered. Quote
slick Posted October 5, 2008 Report Posted October 5, 2008 Yeah, a faulty EGR will cause horrible running condition's. Quote
55trucker Posted October 5, 2008 Report Posted October 5, 2008 Well..if you're at the end of the rope.....perhaps it's time to consider having a scope test done on the engine. Quote
5speedz34 Posted October 6, 2008 Report Posted October 6, 2008 Can you elaborate on "dumped its coolant?" Quote
ManicMechanic Posted October 6, 2008 Author Report Posted October 6, 2008 I half assed the freeze plug using one of the rubber expandable ones... I didn't exactly have the capability of pulling the engine at the time. It still has one, but it's holding quite well for the time being. Quote
5speedz34 Posted October 6, 2008 Report Posted October 6, 2008 Ok, I remember when you posted this. The only thing I don't get is I've never heard of a 3.4 let alone most cars having problems with freeze plugs. And, they make rubber ones?!!! Did the car overheat or anything? Quote
j_mezz Posted October 6, 2008 Report Posted October 6, 2008 How long did it sit? Possible bad gas? Quote
ManicMechanic Posted October 6, 2008 Author Report Posted October 6, 2008 Ok, I remember when you posted this. The only thing I don't get is I've never heard of a 3.4 let alone most cars having problems with freeze plugs. And, they make rubber ones?!!! Did the car overheat or anything? I know...The previous owner had replaced the freeze plugs once before at the hands of a shop owner in California (girl on vacation in nice car=$$$$$$ for shop owner ) No, the car never overheated because I caught it beforehand and had it towed home both times. I haven't gone to get the EGR gaskets yet so as soon as I get done eating, I'll do that and report back. Quote
slick Posted October 6, 2008 Report Posted October 6, 2008 While you have the EGR off, spray some carb cleaner into the ports of the EGR to clean out any junk that's inside of it. I always seem to get a lot of carbon buildup out of the EGR. Quote
ManicMechanic Posted October 6, 2008 Author Report Posted October 6, 2008 Done...Not gonna say anything right now...But we'll see... Quote
5speedz34 Posted October 8, 2008 Report Posted October 8, 2008 Hmm. Do you know when the intake gaskets where done? Quote
ManicMechanic Posted October 8, 2008 Author Report Posted October 8, 2008 Hmm. Do you know when the intake gaskets where done? I did them last July. Quote
5speedz34 Posted October 8, 2008 Report Posted October 8, 2008 Ok, so any updates on the EGR gaskets? Quote
rossg Posted October 9, 2008 Report Posted October 9, 2008 How are the plugs? water in the spark plug holes will cause an arc and you might have this problem. Is the screen still on you maf or have you removed it. My car ran like crap when I took mine out so I put it back in. How is you fuel pressure regulator? Quote
ManicMechanic Posted October 9, 2008 Author Report Posted October 9, 2008 Ok, so any updates on the EGR gaskets? Better...Not 100% but better. I still have a little more work to do to it... Quote
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