So today i started up my engine for the first time in my newly rebuilt LT1. As i figured everything went well. Then after awhile i cut it off to stop all the smoking from my new headers as the paint burns. I start it back up to realize that my coolant was below the sensor so i fixed that and then things went strange, my idle would increase and then decrease and at the end i tried starting it and it idled so low it cut off. I also tried putting it in reverse and the engine just shuts off?

So are these just bugs or the computer is trying to programs its self? Has anyone experienced this?

Thanks, Ryan

 

computer do not program itself. if ur RPM is increasing/decreasing, then check ur vacume/air pump lines, it is possible that u may have a leak or missplaced a line. also check ur feul pressure if u have a gauge
Is ur SES light on?

 

do yourself a favor and replace your coolant temp sensor happens all the time thats all it is

 

or just unplug ur coolant sensor like most, check ur trans fluid since it died out and if the idle is way to low and you put it in gear yes it can make ur car die out by putting it into gear.

 

Sometimes the SES light is on and others it isnt. Today i will try again and see whats up

 

Scan it and see what codes are stored.

 

i thought it would just throw a **** load of codes cause its a new engine

 

Yeah, but some might actually point to a problem...

 

okay yea ill do that. But like any new engine, once it all hooks up there are always going to be those few little problems right?

 

It's normal to have to work out a few bugs. With my last engine I found a vacuum leak, a leaky injector o-ring, and I had to readjust my rockers with the engine running. Then my car ran perfect.

 

okayyyy im about to go up to the shop now so we will see how everything goes!

 

okay so things went okay: I scanned it for codes and only got one: TPS (throttle position sensor) It said low voltage or something like that. That explains everything, i started it up and it was idling at 1500! i put it on reverse or drive and the idle drops so low it kills its self. Then sometimes it will idle around 400-500. Then it will correct itself and idle around 900-1000. Very strange.
Next: I have a starting issue, (for the people who have kept up with my car, my starter mounting was a staggered type. So i have the V6 starter on my car and i dont think its strong enough to start the car instantly, it takes sometime and ahhh it sounds terrible!
Any help?

 

You might need a new TPS. Check the wiring and pigtail to it.
Does the starter screetch? It may need to be shimmed.

 

Honestly, if you did everything correctly, you shouldn't get ANY SES lights upon starting it up. At least I didn't.

You're using a V6 starter? Good lord man, get a REAL starter! It is undoubtedly underpowered. Also check the TPS reference voltage (blue wire) with the KOEO. Should be around .65v when at idle and increase to ~4.5v at WOT.

 

^Hey now that's not true. I had bought a motor, guess what it needed a new knock sensor and coolant temp sensor. Can't do anything about that, wouldn't know til it was running.

Well could have checked the knock sensor resistance, but really didn't think of it at the time. Suppose that would have been nice to catch while it was on the stand and not in the car with coolant in the block.

 

^^Was that the one you got from me? They worked when I sold it to ya..you had it sitting for a while so it wanted to give you hell..lol


To the OP.. I would put the right Started on it and check the wiring on the TPS.

 

You're probably right, it sat there in the garage for over a year, it could probably see the car it was supposed to go into and was getting impatient. Just made my first long distance trip with it, I'm in PA at the moment. Also just replaced my upper and lower radiator hoses, can't complain when you get 180k and 15 years out of a hose!

 

Nice..glad to see it held up for the trip.