Hey guys I just did a compression test on my 92 d16z6. I got good results. 170,170,170,170. I was QUITE surprised. My question is, does this consistant compression rule out the possibility of bent/stuck valves?

 

why do u ask about bent or stuck valves?
results looks very good no need to worry, well unless u hear/feel sumthing different.

 

with those numbers i would assume you dont have any bent valves, you could do a valve adjustment if you are getting a noise or something of concern

 

well the weird thing is I sometimes get exhaust coming out of my intake manifold.

This is what seems like is happening. When i retard my timing I try to start and then exhaust gases come out of the intake manifold. And then when i advance it, it seems to be fine. This is just from what i've seen today so the answer is not final. I could probably try starting it tomorrow w/ the timing not retarted at all and have the same **** happen again.

I dont know if ignition timing could cause exhaust gases to shoot out of the intake manifold, but... i duno, thats why i was thinking maybe some valves might be stuck or bent. what do you guys think?

My main question is can retarted timing cause exhaust gases to come out of the intake

 

why are you retarding the timing. it needs to be set at 16 degrees. 170 is good. you don't have a bent or stuck valve. Check the valve adjustment. Make sure that they aren't too tight. Which I doubt. It's backfiring out the intake because the timing isn't right.

 

Make sure your valve timing is spot on before adjusting the timing, then the ignition timing should be set to stock 16*. Over advancing will cause detonation... if the detonation of the fuel/air mixture in the combustion chamber happens while the intake valve is still open, you'll get your exhaust gasses in the intake manifold, but I don't even think it's possible to advance that much and still have it run.

 

Hmm. that's weird. Because when I set my crank to TDC, my cam gear is also aligned up with TDC so I think it's on the dot.

Is it common for the ignition timing to somehow un-adjust itself? There were times when I set it to 16* and it still had the problem w/ smoke out of the intake.


btw. hybridcoupe. Are you suggesting that the backfire is from the ignition timing like ^ said, or are you referring to the cam/crank timing

UPDATE-

I think I know what I did wrong and why i was thinking it somehow unadjusted itself. I was reading through the helms bible and noticed it sayd 16*BTC @ 650 rpm. Maybe that's what my problem was.

 

i accidentally retarded my timing too much like 5 or 6 degrees over stock........haha.. when i hit boost, it felt like ****.....

but one thing i noticed was my spooling was louder and so was the BOV......

 

Weird. I tried to set my timing to 16 degrees at 650 rpm but I couldn't get the car to idle at 650 rpm. it was like at 900. So i just set it 16* at 900 rpm.and i just was messing w/ my car. it started up fine a few times and then it did it again.

A weird noise like running a screwdriver over a washboard really fast. like VvvvVT lol.


Anyway do u think im doing something wrong w/ the timing? Does anyone know why my car isn't idling at 650 rpm like it shoudl even when i let it warm up for a long *** time?

 

btw do you guys think a corroded tranny ground wire could cause this problem at all?

btw can anyone recommend a cheap fuel pressure gauge and a site to buy it from?

 

Yes...I was refering to the cam/crank timing. as for a fual pressure guage...try to find one that hooks to the top of the fuel filter. Any parts store should have one.

 

let the car warm up enough for the fan to come on once, bridge the SCS service connector near the ECU, unplug the IACV (to make it idle at 750, it won't go lower) and adjust the timing. That's the only way to do it.

 

What is the iacv? Is that the vacuum tube that connects tot he FPR? Cuz i noticed when i unplug that the idle shoots to like 1500rpm. I'm not at home right now but i can look at the helms later i guess.

so do u think the ignition timing is most likely the problem?

 

bumpy

 

the IACV is the Idle Air Control Valve, it's on the very back of the intake manifold plenum and the plug is on the bottom. When you unplug it, the car has no choice but to idle at 750.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Plugg’d &raquo;</TD></TR><TR><TD CLASS="quote">so do u think the ignition timing is most likely the problem?</TD></TR></TABLE>

It's just one more thing to rule out before continuing on to find other problems. You have to solve each problem one at a time.

 

like CycloneBlue_1.6EL stated. did you jump the service connector before you check or change the timing?

 

yes i jumped the green white/brown. Just out of curiosity, what does jumping those wires do?