David Dale

today i decided to re-check my timing to make sure it was good. Well it is, but since i have some sort of problem with my car it advances itself and then goes back to the mark, and it does this whenever my car's exhaust starts to pop repeatedly. It seems like a misfire.

My question is should i see the T2 mark when i check the timing?

because i can't see the mark when i do it, and it seems like it isn't firing as often as T1, like the firing is kind of patchy. What could be the cause of this? Is this issue strictly ignition related or could there be more causes?

thank you

arghx

iTrader: (3)

first of all, did you jumper the initial set connector when setting the timing?

David Dale

I didn't adjust the timing this time, because it was right on...but i know for a fact i didn't do it last time i set it O.O

Would that somehow cause one of these problems?

J-Rat

iTrader: (2)

All the ISC does is disable the BAC....

David Dale

ok... well either way when i was looking at the timing i did have the initial set connector grounded idk if that makes a difference. But i'd still like to know if i am supposed to see a mark lines up with the needle when i check the T2 spark?

Aaron Cake

iTrader: (1)

Is the idle speed at a factory 750 RPM? Above 1000 RPM, the ECU advances the timing.

David Dale

Well that's kind of the problem...you see, i can get the idle down to about there while it is warming up, but it has problems maintaining a stable idle, im almost 100% positive that there isn't any vacuum leaks but at some moment during the idle its like something just turns on or switches something, and all at once my idle just goes to hell and starts popping etc. and my car raises its idle to about 900-1100 and fluctuates somewhere around there.

darkblaze

Check your Spark At the leading Plugs. i have almost the same Issue and My Leading Coil is Dead have to get one from the wrecking yard tmr

David Dale

my leading coil is fine i've checked 'em a couple of times...its just the trailing...

i was checking my acv just for the heck of it today and i could feel little pops coming from the acv when i was doing the tests on it...i wonder if this may be the issue, and if my ignition problem is a result of this?

darkblaze

well i got my leading coil and she PURRRRRSSSS now just have to figure out why she idle bounces.

RotaryEvolution

iTrader: (30)

check for vacuum leaks with the engine running with a can of carb cleaner, just be careful spraying it around the exhaust and ignition wires when the car is hot. if the car smooths out then you have a vacuum leak in that area.

first set the TPS by warming up the car and shutting it off but leave the key in the on position. hook up your voltmeter negative lead to the negative battery terminal and the positive lead to the green wire off the TPS connector by backprobing it. with the throttle at idle adjust the TPS to read 1 volt on the meter and then do a slow sweep of the throttle, it should smoothly go up to ~4.5volts, if it has any dips or spikes then replace the TPS and readjust it.

the T2 mark won't line up with any marks on the pulley while the engine is running. at idle the L1 will line up the the mark on the driver's side of the pulley and the T1 will line up with the passenger side mark on the pulley. if the car isn't idling down then the L1 and T1 will both point to the same spot on the pulley(stock timing split is at 0 under low RPM/low load situations), meaning your timing isn't at base because the car isn't below 1k RPMs to idle down properly.

also keep in mind if you have wired open 5/6th ports the idle will be slightly bouncy naturally.

David Dale

Well im going to take my car to my friend's shop class to use smoke too be extra certain that there isn't a vacuum leak, so that will be done soon. I set my tps from the voltage at the ecu pin so that i know what the ecu is getting. And i found sleeves for my 5th/6th ports...

i was looking up the sensor voltage on my apexi fuel controller, and the voltage for my afm pretty much remained the same even when i was increasing the rpms...could that be the problem? Sometimes i get a afm code but then it goes away.

Im wondering if my problem is only related to closed loop, because when i first start my car it runs good while its warming up and then it runs bad once it starts warming up. with the emissions on and everything it begins around 13 or 14 afr and ends at 21 or 22

Im regretting not paying you more money to find my problem karack XD

oh yeah quick question, i was checking my acv to make sure it was good, and i noticed that the Haynes manual says no air should be flowing out at certain times...but i can always feel a little bit of air coming out of the acv...and when it is supposed to, there isn't alot flowing i was just curious if this was normal...also when i pulled the hose going to the air pump and i put my finger over it and i can feel little pops coming from the acv when my car does a pop from afterburn...is this bad?

David Dale

Scratch that the voltage for the afm does drop when i rev the engine...

rk970

iTrader: (1)

You could get a vacuum leak from a bad ACV (if the diaphragm is split). A falty TPS can also cause a bouncy idle (check it with a analog ohm meter). Check the Thermo sensor (the one in the thermostat housing) One simple thing that is over looked is gacked up dirty throttle plates.
rk

David Dale

what exactly would be the effect of a split diaphragm in the acv? I know the symptoms of a vacuum leak, but would the be any other ones?

like i said in the previous post theres always air coming from the acv when i tested it according to the Haynes manual. and there's not much coming out... also i mentioned that when i place my thumb over the hose that goes to the air pump from the acv i can feel pops.

thermo sensor...if it was bad would it create a lean condition? or would the ecu disregard it and enrich the air/fuel mixture ?

My throttle plates are pretty clean ^.^

rk970

iTrader: (1)

When the diaphragm goes bad in the acv it will usually pop/backfire through the exhaust between shifts at high rpm..