crazy ka24de swap runs but with issues

[burnin240sx]

We have swaped a 96 engine with 93 manifolds and ecu into a 89 body.We had taken over this project to finish it. the intake manifold was takin apart (we don't know why) and we put everything back on.

we couldn't get the engine to start due to a vacume leak. which was a plug in the intake that was missing. we have fixed the leak and are able to get the car to run but it pop's and cracks when you step on the gas and will not idle on it's own.

I can't hear any other vacume leaks. I am stumped at to why it is doing this. all I can think of is that there is another leak that we are missing some where. Unless there may be some other issue.

Please help

[NISTECH]

is this the same car that wont start in your other thread?

Maybe your MAF is wrong? which car is the MAF out of?

[burnin240sx]

the maf is from a 93 engine. I got the maf sensor code to go away when i found the missing plug in the intake manifold.

[burnin240sx]

any ideas? vacume leak still?

[NISTECH]

Sorry thought you solved it from your prior post. Break out your volt meter and test your maf. It sounds like its out of wack. White wire I believe ,should be your signal wire. Test all three wires though one should have less then.02v which is your ground, any higher then that you need to run an alternate ground in parallel with that one. One wire should be battery voltage and the other,your signal wire, should be in the neighborhood of 1.3 to 1.5 volts at idle and steadily increase as you give it gas, if that signal is off and your other 2 readings are good ,you need to get another flow meter.

[burnin240sx]

i've tryed the maf on my car which runs perfect and it had the same problem. I also tested the wires from the maf connector to the ecu harness pins. the had 0 resistance. I also did the diag in the fsm for checking voltage and it was all good. all i can think of is that it is a vacume leak but i can't hear anything over the exaughts. and i ran the lines myself with the motor out. I removed the egr and put ablock off plate there with plenty of blue rtv.

I hate taking over half *** fixed cars. I can't belive he took the intake fully apart. I'm almost at a point where i don't know what's wrong.

[NISTECH]

what were your readings on the maf? especially on the ground wire.

[burnin240sx]

i'll have to record them and get back to you but i can hear a vacuum leak now that i couldn't yesterday... go figure.

[NISTECH]

Just a note here, if you look at your Maf readings in connjunction with your O2 readings you can determine easily if you are infact dealing with a vaccum leak, even if you cant hear it. A vaccum leak would show up as a low voltage on both sensors. The o2 would be locked on lean [near 0v] and your Maf reading would be slightly lower then normal as it wouldnt be seeing all the air getting in the engine.

[burnin240sx]

genius

[burnin240sx]

well that meathod worked perfectly. I was thinking it was one of the hose's but come to find out it was the EGR gasket. replaced gasket and car run nice with a rough idle. change plugs and it pur's like a kitten.

Thanks for the help. this will be very handy knowledge in the future. Thanks you master NISTECH i am forever in your debt

[NISTECH]

you workin on 2 cars bro?

[burnin240sx]

yeah I'm still learning. I do preaty good but every once and a while i run into a issue that i need some help on.

[NISTECH]

cool no sweat just realized I was working with you on 2 different issues.