Hey guys i finally got my lt1 to "idle" on its own if thats what you'd call it

Problem now is when i have it started the car shakes and idles rough, no backfiring of anysort don't have to hit clear flood mode or anything, go to the rev the car it maybe jumps up a coupl 100 rpms nothing much after letting it run for a couple minutes try to rev it again it sometimes backfires i one point i believe i even fealt a backfire through the intake not sure though. Oil was changed yesterday and smells like fuel already have not pulled plugs yet but i'm sure they might be fouled any suggestions before i take this to a shop i'm running out of time to mess with it.

Things checked so far, FPR line smells like fuel but no evident signs of actual fuel leaking out, had a burnt plug wire but only the boot was slightly burnt cover moved out of the way and re installed.

I have recently put comp xfi 230/236 113lsa cam in, le2 heads/intake, 1.6 rr
36lb/hr injectors, pp 58mm throttle body, longtube headers and ory.

Fuel pump, filter, plugs, wires, almost every sensor is new just looking for sommething to check i have a scanner that reads some of the data i can try and take a video or record the data for anyone whoe can look at it also have the tune i got from mad if anyone wants to take a look at that also



thanks in advance

 

Did you actually apply a vacuum to the FPR? If that is ok lift up the fuel rails and pressurize the system and look for leaks.

double check the correct clips are on the right injectors and correct wires are on the right plugs.

 

plugs and wires are correct, the wires on the injectors are correct also its the same as piston order correct? 1357 and 2468, how would i go about putting vaccuum to the fpr while it was running i pulled the line off the intake and had nothing the line smells like fuel but i've never actually found evidence of fuel in the line.

 

Use your scanner to look at the coolant temp sensor, and the O2 sensor voltages. A faulty coolant temp sensor, or wiring/sensor problems with the O2 sensors can cause it to run excessiively rich. So can having the valves adjusted too tight.

 

the coolant temp is normal i checked that on my little scanner the to 02 sensors that are hookedd up read about .945v but i will double check here in a couple of minutes and see what they read, for the valves i just re adjusted them 2 days ago they shouldn't be to tight i did zero lash and about half turns on all of them for preload.

 

ttt....

ran the car for a couple of minutes yestday o2 sensors are around .945v and lt fuel trim is 7.8%

need some ideas please

 

Under what conditions do the O2 sensors read 0.945V? In closed loop, they should not be steady. They should be rapidly moving back and forth betweem 0.0xx to 0.9xx Volts.

If you only ran the engine for a couple minutes, the PCM would not have gone into closed loop, and the fueling would most likely be based on cold start enrichment, yielding the steady, high O2 sensor readings you reported. That assumes you do not have a working AIR pump, because that would be operating in open loop, and would cause the O2 readings to drop close to 0.

The PCM starts in open loop. The O2 sensors have to heat up (~600*F) and become active, the coolant temp needs to reach 140*F and the engine has to be running for 206 seconds (3 minutes, 26 seconds) in order for the PCM to go into closed loop. You need to scan it in closed loop, and verify the O2 sensors are moving rapidly over the range mentioned above.

 

ill do that today i just haven't wanted to run it so long due to the excess fuel, and the air pump has been removed

 

Not sure you mentioned it, but have you had the car tuned for the recent mods?

 

car was tuned by madtuner, went to go for a start all morning but the plugs are fouled out.... this things a real pain in the ***

 

Exhaust leak?

 

as far as i know of know exhaust leaks the long tubes are brand new and torqued down with gaskets.... 02s also read fine on cold start plugs fouled so i haven't had a chance to look at close loop.


Also before all this when i first got the vehicle together it started up under some throttle for the throttle body wasn't letting enough air in. Car revved freeley then until i let off the gas and it died itself. Out of curiousity could you over adjust a thorttole body set screw? Also a coupl of weeks ago i had it revving up also and it would stop at 4000rpms i figured it was just the valves which i re adjusted so i'm not really sure what the problem could be.

Any other inputes would be awesome, could the seal on the map affect revving i mean its together but it wasn't looking as great as i'm sure it did from the factory, also my map readings never really go down at all even with throttle

 

I know you said your tune was done by MADTUNER but,was it before you installed the 36lb injectors or after?How did you get it to idle down?You could have a intake gasket leak,or throttle body gasket leaking...Last yr I had a similar problem,would not rev up,soaked the plugs,gas in the oil...turned out there was a small tare in the throttle body gasket around one of the bolt holes...

 

the tune was done for 36 pound injectors, i have jet dst though so im gonna tune it for the stock ones because i put them back in, now that you've mentioned it though my throttle body gasket was ripped and i rtv it together to fix it because 58mm throttle body gasket are kind of hard to find but maybe i'll buy a stocker and put it on and give it a try thanks for the reply

 

also i got it to idle on it own by adjusting the set screw and tps