car won't idle
Thread Starter
Junior Member
Joined: Oct 2001
Posts: 77
Likes: 0
From: southgate, ky, us
car won't idle
I really need some help...
My car starts fine cold, but when it warms up after 2-3 minutes, the idle becomes rough, and the rpm "hunts" until it dies. I just installed a nitrous kit 5151 along with purge valve, bottle warmer, and remote on/off switch, so I did take the throttle body off.
I've checked for vacuum leaks using a hose and listening, and a propane bottle with hose to search for intake leaks. I've checked all physical connections, and looked at plugs. I'm running fuel pressure at 50 psi. Also AC Delco rt42t plugs... a little cool, but they are new. Plugs look like their running rich. The coolant fan comes on earlier than it used to, and stays on longer. The car runs fine above idle, seems as strong as ever. In my search, I did find a little exhaust discoloration above the pass. side headers, mayb a small leak, though the hose test hardly hears it. I have a gutted cat and the smog pump removed. The car has sat about two weeks for installation... I did a very thorough, pro job on it, and I noticed more than usual moisture coming out of the muffler and on the floor... it is water, tho, not antifreeze... no fuel odor.
PLEASE HELP!!!
------------------
Jethro
1987 IROC Z 13.92 and 1.92 60' street tires stock engine
My car starts fine cold, but when it warms up after 2-3 minutes, the idle becomes rough, and the rpm "hunts" until it dies. I just installed a nitrous kit 5151 along with purge valve, bottle warmer, and remote on/off switch, so I did take the throttle body off.
I've checked for vacuum leaks using a hose and listening, and a propane bottle with hose to search for intake leaks. I've checked all physical connections, and looked at plugs. I'm running fuel pressure at 50 psi. Also AC Delco rt42t plugs... a little cool, but they are new. Plugs look like their running rich. The coolant fan comes on earlier than it used to, and stays on longer. The car runs fine above idle, seems as strong as ever. In my search, I did find a little exhaust discoloration above the pass. side headers, mayb a small leak, though the hose test hardly hears it. I have a gutted cat and the smog pump removed. The car has sat about two weeks for installation... I did a very thorough, pro job on it, and I noticed more than usual moisture coming out of the muffler and on the floor... it is water, tho, not antifreeze... no fuel odor.
PLEASE HELP!!!
------------------
Jethro
1987 IROC Z 13.92 and 1.92 60' street tires stock engine
Thread Starter
Junior Member
Joined: Oct 2001
Posts: 77
Likes: 0
From: southgate, ky, us
I hate it when ppl dont post a follow up... herIe goes:
The dual prom holder does not work! Additionally, the idling problem was related to bad/too cool? plugs that I put in for the nitrous kit. Apparently, our plugs in the 86 and 87 year are already cool enough... r43TS, remember, many similar engines run up to 45 stock. I kept on troubleshooting, going over all physical connections... changed the O2 sensor, the CTS sensor, took all the plugs out to look at them, seemed fine. But changing them back to the old plug cured the problem. I also listened for vacuum leaks, sprayed propane out of a bottle with a hose attatched to likely intake leak areas... reseated the throttle body... lot of stuff.. but this was a hard one cause it was TWO problems, plugs and Prom holder.
The lesson learned is one I usually stick too.... change as little as you can in a large project, then RUN the car to make sure it works ok.
The dual prom holder does not work! Additionally, the idling problem was related to bad/too cool? plugs that I put in for the nitrous kit. Apparently, our plugs in the 86 and 87 year are already cool enough... r43TS, remember, many similar engines run up to 45 stock. I kept on troubleshooting, going over all physical connections... changed the O2 sensor, the CTS sensor, took all the plugs out to look at them, seemed fine. But changing them back to the old plug cured the problem. I also listened for vacuum leaks, sprayed propane out of a bottle with a hose attatched to likely intake leak areas... reseated the throttle body... lot of stuff.. but this was a hard one cause it was TWO problems, plugs and Prom holder.
The lesson learned is one I usually stick too.... change as little as you can in a large project, then RUN the car to make sure it works ok.
Thread Starter
Junior Member
Joined: Oct 2001
Posts: 77
Likes: 0
From: southgate, ky, us
I hate it when ppl dont post a follow up... herIe goes:
The dual prom holder does not work! Additionally, the idling problem was related to bad/too cool? plugs that I put in for the nitrous kit. Apparently, our plugs in the 86 and 87 year are already cool enough... r43TS, remember, many similar engines run up to 45 stock. I kept on troubleshooting, going over all physical connections... changed the O2 sensor, the CTS sensor, took all the plugs out to look at them, seemed fine. But changing them back to the old plug cured the problem. I also listened for vacuum leaks, sprayed propane out of a bottle with a hose attatched to likely intake leak areas... reseated the throttle body... lot of stuff.. but this was a hard one cause it was TWO problems, plugs and Prom holder.
The lesson learned is one I usually stick too.... change as little as you can in a large project, then RUN the car to make sure it works ok.
The dual prom holder does not work! Additionally, the idling problem was related to bad/too cool? plugs that I put in for the nitrous kit. Apparently, our plugs in the 86 and 87 year are already cool enough... r43TS, remember, many similar engines run up to 45 stock. I kept on troubleshooting, going over all physical connections... changed the O2 sensor, the CTS sensor, took all the plugs out to look at them, seemed fine. But changing them back to the old plug cured the problem. I also listened for vacuum leaks, sprayed propane out of a bottle with a hose attatched to likely intake leak areas... reseated the throttle body... lot of stuff.. but this was a hard one cause it was TWO problems, plugs and Prom holder.
The lesson learned is one I usually stick too.... change as little as you can in a large project, then RUN the car to make sure it works ok.
Thread
Thread Starter
Forum
Replies
Last Post
