runs rough when warm?

[WB1]

Hi all having a problem with my 95 gtp 3.4 dohc. I had to replace the head gasket due to failure while it was apart I sent the heads out to be dolled up got it all together used my new cam setting tools so the timing is right on, It runs great when cold but like crap when hot? Any ideas where to start looking? I have read some things in the forums about the trouble shooting codes my problem is how do I get the codes out of it? And do I need to buy more stuff?

[series8217]

Does it just idle rough or does it also behave differently when you're on the throttle?

[WB1]

runs rough at idle and when you are getting on it but only runs bad once it's warmed up. I gave it some new spark plug wires in hopes that would clear it up and it was no help. Also had a freind try pulling any codes he could out of it but there were none to be had. So I am at a loss of places to look for the problem

[series8217]

My car did that when one ignition coil was going bad.

[WB1]

Thats kind of what my buddy was thinking the problem might be. So I guess I need to pull the 3 coil paks off and check them out. What do those things cost if that is the problem ?

[SappySE107]

Id get a set off ebay if you want to replace them. That or they are about 23 bucks each from the parts stores. Some have had problems with wells or gp sorenson or whatever, but im running 2 of 1 and 1 of the other without problems.

[series8217]

I always just go to the junkyard and get a bunch for like $5 a piece. Bring a multimeter along to test coil resistance. You can tell if they're no good just from that. Out of five OEM parts from the JY for the price of a new one you'll last a lot longer than the aftermarket crap you get at Autozone..

[WB1]

Is this a common problem with this engine ? The car may be 11 years old but it only has 70k miles on it. Thats the only reason I decided to spend the time and money to do the head gasket.

[WB1]

When I remove the coils what should the resistance be? I am guessing if 1 of the 3 is way different then the rest that would be a problem.

[germ]

have you checked the coolant temp sensor?


and what do you mean by "it runs like crap"

what exactly do you mean by crap?

[WB1]

Is that the sensor in the side of the Head? It has no power when warm the exhaust sounds bad when warm vs when its cold it runs great sounds great. The temp guage seems to work fine so would that mean the temp sensor is ok? Im going out to pull the Coil's what should the reading be on the meter for a good coil vs a bad coil ?

[germ]

being that you have a 95, there is a chance that you have 2 sensors. one for the gauge and one for the computer.

i bet the one for the computer.

mine ran like crap as well when it got warm. it was the coolant sensor for my problem.

[WB1]

just started it up to move it and seemed to run poorly when cold to.

[napatiger]

I think the one in the head is for the gauge and the one in the TB is for the computer.
My car gauge would work, but I got error 117, temp out of range, and to find out TB temp sensor unplugged.

[WB1]

I got it It runs AWSOME for the last week or so. Turned out my spark plug wires were cheesd out on me so I replaced them but managed to screw that up and got 2 cylinders crossed . It was worth doing this all myself I learned alot about my car and some new swear words to boot Thanks for all the help Bill