Hi, I re-built my TBI, Replaced IAC, TPS, Distributor, cap and rotor, wires, pluggs (but #8) . I am still hearing the hiss coming from the TBI after acceleration.

I unplugged the TPS connector and there was no hissing from the TBI, but I was still bogging.
Today my car ran good, sometimes bad... Than I tried starting the car few times. Once it started up fine, the other time it started up after a bit of crancking it was running but quite bad. So I turned it off, started it again and the car ran perfect.
The bog is there sometimes, and its not there. At the low end, the top end is still fine and once I get over 35 I am running fine.

I am just stumped of what to do.
Someone said a vacum leak, but there was no hissing after I unplugged the TPS.

I am thinking that there is some kind of problem with the electrical system in my car. Maybe I am not firing right at times.
And my car tends to lean out big time when it boggs.

This all started happening after I changed my cap and rotor and coil. Checked them all, and they were fine.

I need some suggestions of what to do!

 

Did you ever set your timing after the new parts?

 

Yes sir. At first it ran at 8 advanced, I put it at 0 and it sounds a lot better, yet still it acts crappy.

Any more suggestions?


(thanks for helping)

 

I've been searching for hours now, and I've got few questions.


Could exhaust (headers) leak cause the knock sensor to retard the timing???

Could oil preassure sending unit to the ECm be clogged, thus limiting fuel flow???


It most likely feels like at some point in time the ECM will run me really lean to the point where the TBI starts hissing at idle. After a bit it evens itself out.

Could exhaust do this???

I do have a leaky exhaust, especially at driver side header.

LEt me know if I should probably put better gaskets on the headers, or ... I don't know.

 

I doubt its oil pressure sending unit, if im correct it will either tell the ECM YES/NO so either you will get fuel or not.


Leaky headers could cause a lean burn on the cylinders that are leaking. Are you running single or dual O2's? if your running a single and its on the non leaking side that could definately be an issue.

 

THe leaky headers could be a problem, but the 02 is on the driver side where the headers are leaking. I really did not have any problems with leaky headers before I got good gaskets, and they were leaking badly.
Could the leak cause the knock sensor to retard timing.

Can spark knock cause the sensor to mess up too???

I had some knock in the motor, but it came when I had it about 8 advanced base. It went away once I got it to 0. However, I am still having the hesitation problem.

I am just going to fix whatever I can and go from there.

So far, everything I replaced helped a little bit. But the hesitation comes and goes.

Argghhhhhh....

Its probably something stupid..

 

Hiss? Could you define hiss a little, is it a constant 'sucking air' noise? Or does it come and go while idling?

It could be a vacuum leak. You'll need to re-inspect you're work, especially if you had you're throttle body apart. Spray some Carb-Cleaner at the base of you're throttle body while it's idling, and all along where the intake meets the heads.

If your'e RPM immediately goes up, then back down again, you found you're leak. Make sure you're TBI gaskets didn't tear when you re-assembled it back together, too....

BTW, you did disconnect the battery before you replaced you're ignition components, right?

 

I did when I replaced the cap and rotor. i did not dissconect it when I replaced the distributor.

I did the car cleaner trick too, and it did not work either on the TBI or the intake.

I am suspecting the TPS to be the culprit. I think its missadjusted.

here is the pic.

 

I know I have one bolt holding it right now, but its a lot better than before when I could move the old one.

The circled thing, can I adjust that???


I'll put some more pics on the TBI board, cuz those guys specialise in the TBI's