386kustoms

iTrader: (2)

so here is my issue. i bought a rotted out trans am 1985 2 years ago. pulled the engine and trans out. tpi 700r4 and installid it in a 55 chevy truck. the motor ran great when i pulled it. well im just now getting to the project and have the motor trans ecu and harness in truck. it starts up fine and idles good. if you punch it it reves up great but if you try to give it a little gas it sounds like it wants to die. very bad flat spot. this is what i have done

i had to replace inj and i bought a refurbished set off ebay. i needed the inj off the orig motor for a nother trans am i had
i have a brand new fuel pump, reads about 40 at idle and does move up a bit when reving
checked tps reads 540 and when i move throttle up it does move up very steady
car curently does not have exhaust it is going to shop on wend but does have stock manifolds on it.
does anyone have any other idea where i can start looking. i put a timing light on all wires and it seems to be fireing good.

could the mass air flow cause any of these issues? also could the refurb inj have anything to do with it? it almost feels liek when i rev it it gets teh air but not more fuel. i have tripple checked all my ecu wires and everythign is hooked up correctly

johng1

iTrader: (1)

Vacuum leaks can cause some crazy problems with these motors. See if you can borrow someones smoke machine and plug it into a vacuum line and see if it leaks out anywhere.

I bought some injectors off of ebay and they have worked fine. If you have got this far and the motor starts and runs I would go ahead and move forward. Get everything hooked up on the truck (ie maf, air filter, 02 sensor, and all the other sensors) once you have everything hooked up then you can start trouble shooting.

I just put a tpi in a 56 2door hardtop. We started trying to trouble shoot a few things before we were completely finished and we ended up just chasing our tail. Once everything was completely finalized most of the problems worked themselves out.

386kustoms

iTrader: (2)

update if you can call it that. had the car at my mechanics shop all day. did flow test on inj hooked up there scanner and he said everything is in perfect parameters and can not figure out for the life what is the problem. he said car is running a little lean but everything is doing what it is supposed to be doing. told me to start with a ign modual but i dont think he thinks that is what it is. he said next is getting a prom the only thing not hooke dup is the charcoal canester everything else is there so i can not see the reason i would need a prom put in. anyone have any other ideas befor i go crazy trying to figure this out.

battman

iTrader: (2)

What do you have base timing set at? Do you still have the EGR installed on it?

Steve Mack

iTrader: (5)

If your charcoal canister is not hooked up are you venting the gas tank to the open air?Is the canister switch still hooked up.You might have a vent line sucking air.Did you plug the small pipe under the throttle body.

GCrites80s

What kind of scanner did he use? It needs to track BLM and Integrator in addition to the ones you see normally such as O2 and spark. BLM and Int can be going nuts and O2 won't be the wiser since it's last to know.

386kustoms

iTrader: (2)

im not sure on the scanner but he told me everything was where it needed to be, yes the vent line going to the canister is plugged timing is set at 7 deg.

i have gone over everything possible this is what it is doing exactly

when it is cold it starts right up, if you go to rev it it will fall flat on its face. after it warms up a bit you can rev it but it is not smooth and it has a definite miss, now for ***** and giggles i was playing with the tps, i didnt have my mutimeter on me but i moved it just a bit and the idle kicked up abviously, well i went to rev it and it was much smoother. i could almost live with it, but i know the numbers are way off. to me it seems like the car isnt getting all the fuel it should be getting. the tech also said to him it seems to be running lean and you can hear it backfire in the intake here and there. i have sprayed stuff all around intake checked all lines and i dont see or hear any vacume leaks. im curious if one or two of the injectors are not working. the teck said he did some test and they all were ok but i have learned never to trust anyone.