can"t find bad idle and loping....

[mk3tattoos]

I have been trying to figure this out for a couple of months now. i don't seem to have any vacume leaks, fuel leaks, or exuast leaks. I did notice the ground to the coil pack was hanging on by a thread. Would that cuase the problem? It also will idle good for a little bit.

I think it might have something to do with the tps, or ecu. i will put a list of mods done, but this started right before i put all of them on. I also have sound clips of the car before the bad idle and after.


fresh 7mgte
ct26 57trim
rc550
sx afpr
no j tube
walbro 255
lex afm
apexi intake
blitz nur spc.
titan ddp
safcII
timing set at 8 degrees
bosch 110 bov
synapse bov
this was 6 months ago or so.
http://www.youtube.com/watch?v=psAM7Hx-JV0


this was last month and you can hear the loping or missing.
http://www.youtube.com/watch?v=dclFvVvH1FI

 

[mk3tattoos]

DAM NO IDEAS......................... OR COMMENTS AT LEAST!!!!!!!!!!!!!!

please shed alittle light:love:

 

[gaboonviper85]

fix the ground and go from there....codes?

 

[mk3tattoos]

no codes. how do you do a block test. i went to auto zone and asked for a block test kit and the guy brought me a bottle. told me to put it in the coolent system and run the car and if the exhaust is yellow then its bad.

is that realy how it goes? that just does not seem right.

 

[gaboonviper85]

No....a block test is where you add a chemical to the coolant and depending on what color the fluid turns will tell you if carbon monoxide is getting into the water (aka bhg)....can you pull your spark plugs and take good pics of the electrode ends?

Also fix the ground wire...this doesn't sound like a block issue...seems like fuel/spark.

 

[jdub]

The coil pack ground should not have an impact...it does need to be fixed though.

Set timing at 10 deg with the diagnostic block jumped.

What brand plugs & plug wires and have you tested the wires for resistance?

Your AFR looks good to me.

 

[RoadRaceMK3]

The coil pack ground should not have an impact...it does need to be fixed though.

Set timing at 10 deg with the diagnostic block jumped.

What brand plugs & plug wires and have you tested the wires for resistance?

Your AFR looks good to me.

x2 on the AFR. 14.0-15.5 is usually considered a decent idle especially if it's hanging around 14.7 most of the time.

I would definitely change the plugs/wires and regap new plugs to at least take that out of the mix if you haven't already.

 

[mk3tattoos]

i just put ngk 3307 and gapped them to .028 with msd wires. amd the low idle after warm up did not get better, i will put a new video up from a cold start. thanks for the help! keep it coming.

 

[mk3tattoos]

here is a sound clip of my idle. let me know what you think. thanks

sory wrong video i need to edit!

 

[grimreaper]

what are your vf's at?

did you tune with the safc yet?
does yours have an extra blue wire that is not used?

 

[mk3tattoos]

what are your vf's at?

did you tune with the safc yet?
does yours have an extra blue wire that is not used?

i have not tuned with the safc yet due to the bad idle. and having a xs bov vented to the atmosphere. i just installed a bosch 110 and ordered a hks ssq with hard pipes. so as soon as that comes i will tune the hi throttle.
Idid not want to tune low throttle, but can I?
i will check the vfs in the morning, i cant remember off hand.
I'm pretty sure there ws a blue wire but let me check that to. oh and why?

so here is the video. i try and hold the idle @ 40sec into it. You can hear it breking up and even missfire here and there.
It goes realy lean into the 17:1 AF's, while the idle is just crap!
http://www.youtube.com/watch?v=xkApOTHtMLU

 

[S.A. supra]

Sounds like a vacuum leak. When you get on it does it miss like that? My car sounded like that. It turned out to be the tb gasket. It ran great on the high way, but when i came to a stop it would loop like that.

 

[grimreaper]

check your vf's. The extra blue wire can be tapped into the vf signal and you can use the safc to look at those (easier then having to pop the hood every time).

 

[mk3tattoos]

check your vf's. The extra blue wire can be tapped into the vf signal and you can use the safc to look at those (easier then having to pop the hood every time).

ok the blue wire is hooked up. but i took everything off the top of the engine to get to the TB. so i can not start it right now.

I removed my TB so i could clean it out one day about 6 months ago. So i was doing some research and came across a comment were it said not to use carb leaner if the tps is on there. Is that true did i ruin my tps?

I have a couple more questions on the TB. Do you have to replace the gasket on the TB after taking it off?

#2 should i set the TPS and then the timing just to make sure Its all good?

thanks for all the help so far!

 

[mk3tattoos]

Sounds like a vacuum leak. When you get on it does it miss like that? My car sounded like that. It turned out to be the tb gasket. It ran great on the high way, but when i came to a stop it would loop like that.

I always thaught that a vacuum leak gave a high idle? i am replacing the TB gasket in the morning and replacing cam cover gaskets also. i hope this works:aigo:

 

[jetjock]

^ Although I've ignored it for years it's time to set the record straight about that. EFI 101 tells us vacuum leaks on L Type (airflow based) induction systems have very little effect on idle speed. That they do is a myth that needs to die. It's true disconnecting the vacuum hose on your fuel regulator will increase idle slightly but that's due to mixture enrichment. Other pirate air entering an L Type system has minimal effect on idle speed. It effects idle quality however and leaks do effect idle speed on D Type (pressure) or carburetor based induction systems. The bottom line is this: if your engine has an AFM and the idle is high by anything more than around a hundred rpm or so it's not a vacuum leak...

 

[mk3tattoos]

^ Although I've ignored it for years it's time to set the record straight about that. EFI 101 tells us vacuum leaks on L Type (airflow based) induction systems have very little effect on idle speed. That they do is a myth that needs to die. It's true disconnecting the vacuum hose on your fuel regulator will increase idle slightly but that's due to mixture enrichment. Other pirate air entering an L Type system has minimal effect on idle speed. It effects idle quality however and leaks do effect idle speed on D Type (pressure) or carburetor based induction systems. The bottom line is this: if your engine has an AFM and the idle is high by anything more than around a hundred rpm or so it's not a vacuum leak...

great info! But what would make me idle at 500rpms but then go up just alittle (6500 rpm). could it have been from me taking off my TB and not know what i was getting into?

 

[grimreaper]

^ thats a simple task man, as long as the gasket was good/new and everything was tightened up and reconnected i cant see that being a problem.

vf's yet? is the dashpot still there and working? How does the ISC test out? have you pulled it apart and cleaned it? ANY worn vac lines or hoses after the afm (ISC hose, Bypass valve lines..) All vac lines ziptied? Pinch the PCV line to tb connection and the ISC hose from the post afm connection closed. What does it do? This is assuming you got the top back together... Any seals leaking on the motor? Is that valve cover seal fixed?

 

[mk3tattoos]

^ thats a simple task man, as long as the gasket was good/new and everything was tightened up and reconnected i cant see that being a problem.

vf's yet? is the dashpot still there and working? How does the ISC test out? have you pulled it apart and cleaned it? ANY worn vac lines or hoses after the afm (ISC hose, Bypass valve lines..) All vac lines ziptied? Pinch the PCV line to tb connection and the ISC hose from the post afm connection closed. What does it do? This is assuming you got the top back together... Any seals leaking on the motor? Is that valve cover seal fixed?

VF's are still unknown, I am working on putting it back together soon. just trying to take my time and check everthing you guys tell me to check.
Dash pot is there but not sure if it is working. how do i check that?

I was going to test the ISC in the morning. Should i clean it out first and then test it, do i use electronic cleaner to clean the ISC?

all vac lines are new but not zip tied, so i will do that.

When i pinched the lines right before i took everything off and it died instantly.
I went to toyota and got new gaskets, and the rubber washers.

Oh, and i need to change out the o-ring on the CPS, but i still need to make sure that it is leaking.
thank you GRIM i appreciate all the help, i will report back as soon as I'm done working my ass off tommorow!

 

[mk3tattoos]

ok i jusst found a problem, when i removed the TB the dash pot had no vacume hose on it. There was fuzz coming out of the end, i looks like the hose broke off.

Do you think this could be the problem? and were doese the dash pot get its vacume? I can not find were the stupid thing goes!