Is it pretty common for the car not to stay running in park with a stock stall and bad coolant temp sensor? I can keep it going with the pedal but when i let off it's either a hit or miss, sometimes it'll stay running and other times it'll die, when it dies it takes about 15 seconds of constant cranking to get it going again. BTW this is right after my heads and cam swap with no tune and 2 minutes of driving time, i'm getting the TC installed tomorrow and i'm also replacing the coolant sensor. Just wondering if this is something i should be worried about.

 

Those should have no effect on the car running in neutral/park.

Something else is off.

 

Ever broke one Mike? I was at the track with a friend when he broke the plug in on his. If I stood and held the wire so it would contact the motor would start and run fine. Pull the wire and the car would barely run.
He went and got a new sensor and ran 10s on spray the rest of the day.

 

Another thing I should probably consider is the size of the cam, and the car is also running very rich.Another thing I noticed is the engine likes to bounce from 400rpm or so to 1100rpm I think the correct term is "hunting". It will usually do this for a few seconds and eventually die but sometimes it'll hang in there and idle for a while.

 

Mine is currently broken, i.e., the low coolant light goes on/off. Not exactly physically broken in two pieces, though.

Maybe I was thinking of the wrong sensor....

 

If it's a larger cam (230 duration or above), you'll need to get it tuned to prevent it from doing that... it's hunting for idle.... Most people (tuners alike) may need to drill a very small hole in the TB to get it perfect.

 

Yeah you were The coolant temp sensor doesn't throw a low coolant light.

It's already got a small hole in the TB, i'll drill a slightly bigger one to see how much that helps. I pulled the transmission out this afternoon, tomorrow the stall is going in.

 

I didn't even think of the low coolant sensor because they only used them on 98-99 LS1 cars (his sig says 01) then dumped them because they're so flakey.

 

Don't drill the throttle body! The car just needs a tune. The table that sets the amount of idle airflow is based solely on coolant temp. The car is probably going to a default air level which isn't enough for your bigger cam. Just fixing the coolant temp sensor might help, but you really need to give it more air from the IAC, which is a tune.

-Geoff

 

I'm not trying to avoid a tune, but i do need to get it running safely so i can drive it to the tuner which is 45min away.

 

Don't drill holes until you get a tune.

Tune first, then drill a very small hole if it's still hunting for idle.

Mike

 

Will do, thanks for all the advice

 

all you need is an idle adjust. wut size is your cam, if it is a 236/236 then you require an idle of 850 rpm, and every 5-7 degrees or so after that it is another 50 rpm. after that you should swap your o2 sensors for a lean burn so the fuel will burn rich when idle and drop off just under 12.8 or so above 2500 rpm, that way you get a good clean idle and awsome rpm after 3000 rpm