Idling Issue

[Noizeof86]

Hey everyone, new to this site...pleasure to be around fellow TR ppl. I purchased an 86 T Type about six months ago. Here's my problem. Car has a few issues I need some help diagnosing. Idling Problem. Hesitation. Intermittent Overheating....here it goes. Upon cold start up, car will start and run rough for about 10 seconds, feels like a dead miss. As soon as the misfiring subsides car loses rpms and dies. Upon restart the miss is totally gone but engine idles way up, then way down to the point of a near stall. After about 5 minutes of this starts and dies crap, car will idle just fine once warmed up. I've reset the iac and tps all within range, cleaned throttle body, and checked EVERYWHERE for a vacume leak. Car has a Red Armstrong computer and chip in it, i've been told those are outdated junk. Now after car warms up to its normal 160 degrees, it runs great except for when its idling and you "goose" the gas pedal briefly, it hesitates and sputters a bit. Now the overheating issue...While driving normally, no heating up, runs right at 160. But if i lay into it for any amount of time at WOT it will go up to around 210. Heater will blow cold air. Getting air pockets in cooling system some where. I replaced the Valve cover gaskets and there was a little bit of freakin antifreeze on top of the drivers side head!!! Cracked head? head gasket? Alright i hope you guys can point me in the right direction. Mainly concerned about the idling and hesitation. I've got an engine im building for it on a stand (so the head deal isn't much of a concern) and i want the running problems to be resolved before i install the new motor, that way if it runs bad i know its a problem i've created and not just a worsened pre existing one. BTW i don't know if you guys follow the NHRA at all, but i work for tim wilkerson here in springfield ill. Anyway...sorry to unload on everyone but i have faith you guys are my last best hope to solve this frustrating idling problem. Thanx, layke.

 

[Nasty]

Coolant on top of head under valve cover. Head gasket or cracked head would seem the obvious. It would explain your air pockets, but running 210 under a sustained load may not be a problem. These cars original ran in that range to start with, the 160 thing is usually a result of a 160 thermostat & chip adjustment for the cooling fan (as well as a good radiator). Additionally, a cracked head or head gasket could explain the hesitation/performance issue you have. Pull the spark plugs and read 'em, 1 or 2 may show signs of coolant or lean conditions in the area you seen the coolant on the head.
Fix the coolant issue first, it can only lean to engine failure...coolant in the oil will kill bearing surfaces at the very least. I would not be surprised if it runs ok after that, but those symptom could mean many things.

Check the plugs.
Pressure test the coolant system to see if it holds pressure.
Perform a cylinder compression AND LEAK DOWN TEST.

These are the first things I would do. The info you get from these would dictate the next steps to check or repair.

 

[Just a Six??]

Hi, since your main concern for now is the idle have you checked the info here? Vortex Turbo Buick Performance Lots of great stuff.
Also you do know about Turbo Regal Web Site I hope.
Thats our bible for these cars.


PS: I would get new chip from Eric at TurboTweak Home to start with!

 

[Noizeof86]

Thanx alot guys. Im gonna get ahold of the turbotweak people. Seems to be the popular response i've been getting. The guy i bought the car from stated that he'd put a red armstrong computer AND chip in it. Now, when dealing with trying to get a chip from turbo tweak to help the idling/hesitation, wouldn't the fact that the computer supposedly isn't stock cause a problem for them to burn a chip for me? Maybe i should by a factory computer and THEN have them burn a chip for that one?? Its got 55lb injectors and a precision turbo set at 16lbs. This is really frustrating to me, im basically dealing with a basket case under the hood. Don't really know EXACTLY what the previous owner has done to it. Sry for the vagueness, and thanx for your patience everyone. layke

 

[GSTOY]

You might also put a vacume guage on and see what kind of vacume your dealing with. That would cause the idle to go up and down..vacume leaks are killers on these cars.

I would also suggest a scanmaster or powerlogger so you can see what's going on under the hood. This is a tool that is invaluable in troubleshooting these cars. Without these, you can chase your tail for a long time, and buy a bunch of parts that are probably not needed...knowledge is power!!

Steve

 

[Noizeof86]

Thanks buddy, like i said i have checked for vacume leaks ALOT haha. Never with a vacume guage, just the ol carb cleaner. Car has a scanmaster in it too. I used it to set the IAC and TPS. I was curious though, i've noticed with alot of street chips, similair to the one Reds thats in mine, the manufacturers require at least one screen in the MAF, I have the stocker on mine and it doesn't have any screens...could this cause a noticable problem??

 

[Noizeof86]

Oh one more thing...i unplugged the maf while the car was running and it died. Is that normal?? Also unplugged the O2 sensor for the hell of it and it idled just the same. Normal??

 

[XLR8]

The car shouldn't die with the MAF unplugged. I would add a screen to the MAF as no screens can mess up the calibrations.

 

[Noizeof86]

anywhere where i can get just a screen for it?? or maybe a way to fabricate something that would work?? I believe i fixed the cold start issue today. After cleaning the tb and setting the tps and iac, i was unaware that i should've disconnected the power wire for the ecm so it could re learn the new adjustments. The car had been sitting all night, before i started it tonight i unplugged the ecm at the orange wire under the hood for about 5 minutes, reconnected, started and idled great. First time in months.

 

[Noizeof86]

also could no screens in the maf cause the hesitation??

 

[turbojd]

also could no screens in the maf cause the hesitation??

It's possible, it will screw up the calibration readings, I would put the screens back in or try another maf and see if that cures your problem.

 

[Just a Six??]

Post in Parts Wanted for a screen. Sure there are a few who can help you out. I gave away at least 3-4 of them from my spares over the years.

 

[Noizeof86]

sounds good ill post in parts wanted tonight. Thanx. How do they install?? just snap in? should i put BOTH screens back in??