stubling or detonating?

[Turtle TR]

HELP: stumbling or detonating?

HELP, I posted this on the hot-air section:

Here's what happend and is happening. On Sunday afternoon, I ported and installed a turbo exhaust compressor elbow from an 86/87 GN. Noticibly the wastegate puck arm is a little taller and I had to lengthen the actuator rod to make up for its height. I had the wastegate set to 15psi before the mod. after installing the elbow, I took the car out and blasted it on the road, even with the rod lengthend, I hit 20psi!!! Drove the car back home, nothing wrong with the car. Next morning, on my way to work, I had a slight stumble, just as the car was going into 4th gear OD at about 2000rpm, during regular traffic. I thought nothing of it. going back home, it did the same thing, but it wasnt a constant thing. This morning, it started stumbling more as I drove off. It wouldnt stumble if I got on the gas hard, and on the freeway, it started stumbling really bad at 2000rpm on the freeway coasting on 4th gear OD. One other thing, I ran xylene on Saterday for the 1st time. I had about 1/2 tank of 92 and poured in 4 gallons of xylene and 4oz of Marvel's Mystery Oil. The car ran really good on it when I raced this past weekend, though, I was thinking it was a bad mixture at the end. I'm going to refill my tank with 92 this afternoon to dilute the 92/xylene mixture. The only thing I could think of of this happening was my sparkplug wires might've been knocked loose while I was taking off the old elbow or during installing the new one, or I have a fouled plug. I'm going lengthen the rod more to see if things change. I don't know, but what I might think is stumbling, could be detonationany suggestions or ideas will be greatly appreciated.
Thanks,
Turtle

 

[TURBOV6]

Too muchy boost!

You should check with a scantool for trouble codes. Bad MAF?

 

[Turtle TR]

No codes.

No codes. I stuck a paper clip to see. 12 12 12 12, so no codes. I went to put gas down at the Kapahulu Union 76. It still pops and stumbles. Maybe it hasnt gone through the lines thoroughly. I was going through the search, possibly my fuel pump is going bad, and the thing that agitated it must've been the xylene mixture. Other factors I have to figure out too. Maybe my O2 got shot? though, I dont know if that causes stumble. hmm...maybe. If there were to O2, or a bad one, wouldnt it cause the car to run rich? maybe that's where the pop and stumbles are occuring. I'll hook up the 'el snap'o on'o scanner tonight and let you guys know what's up. I may end up puting the stock elbow if that's causing it. which I highly doubt. I'm going to change out the plugs as well. CRAP!!! The car gremlins are acking up again!!! If this keeps on going on...I might just buy another TR or an engine as soon as my taxes come in. Jackson, is that retired cop still wanting to get rid of his GN?

 

[BADDGUY6]

Re: HELP: stumbling or detonating?

Originally posted by Turtle TR
HELP, I posted this on the hot-air section:

One other thing, I ran xylene on Saterday for the 1st time. I had about 1/2 tank of 92 and poured in 4 gallons of xylene and 4oz of Marvel's Mystery Oil. The car ran really good on it when I raced this past weekend, though, I was thinking it was a bad mixture at the end. I'm going to refill my tank with 92 this afternoon to dilute the 92/xylene mixture. :any suggestions or ideas will be greatly appreciated.
Thanks,
Turtle

Too much Xylene Mix 4 gals. Xylene into a "FULL" tank of gas. And change your fuel filter. Xylene cleans crap out of the tank. fuel filter might be full of Crap

 

[Turtle TR]

Thanks Guy, I just remembered that too. I have a spare fuel filter laying around in my tool chest. I'm going to change out my spark plugs as well. I rememberd one time I had boost spikes, which resulted from a bad plug. I hope my plug wires are ok. I once tried to run my car without the filter, exposing the maf. but, that was a long time ago. it had the similar bogging and stumbling. I'm going to check voltage from the MAF too. MAN!!! 1st Code 31? now this?

 

[Turtle TR]

I changed the fuel filter, and I hooked up the scanner. I had a Code 22. I checked the voltage, Its at .42v and 4.70 at WOT. Bad TPS? is that why I'm getting these wierd stumbles? it's getting worse. CRAP! Can a bad ignition coil pack or module cause this? I changed out all the plugs, I'm pretty sure the wires are still ok. man...no track time for me for a while.

 

[Turtle TR]

I rested for a while, and went back at it wit the car. hooked up the scanner and found the TPS was at 0.04v I reset the IAC and re did the TPS, all is fine. though, I am still registering a soft code. the 22 which appears off and on. the TPS could be bad. I have it now on .44v and 4.79v WOT. My IAC varies between 40-50. Mt dad and I decided to check the MAF. The ECU didnt show a code 34 but i tapped the MAF to see if there's any change, no change in reading through the scanner, then the scanner suggested we take off the plug and listen if the idle smoothens out. So..I did that..and it smoothed out but, it still had erratic idle at some points. I also noticed that the smell of the gas was getting too rich. the exhaust fumes were burning my eyes and nose. Maybe my O2 could be a likely problem as well. It's happening again, and this is worse than the code 31 I had I'm going to further test more things on the car, my dad took his meter to work so we couldnt test any other readings. Soooooo...to be continued.

 

[Turtle TR]

I drove my car today going to work, hardly any stumbles, just upon acceling the car from a stop. Fricken intake sounded like it was sucking in more than it could take this morning, I think it's because it was in open loop. it calmed down after what I figure was closed loop. the idle is still erratic, kinda misfiring a little. possibly my coil pack is going and module going. I lengthend the wastegate rod again to about an 1/8" and I still hit 20psi.. I wonder if the wastegate is stuck? I'm going to change out the elbow today when I get home and see if there's any difference. I doubt the elbow has anything to do with this but, all the bad things started right after I changed the elbow. I'm pretty much leaning towards the idea that the MAF is going out too. the above post said that I removed the filter off the MAF once and I tried to run it, and there was a huge stumble when I did that, though my engine wasnt missing like how it is now. So there could be 2 possiblities, both the MAF and the Coil pack crapped out when I put too much load hitting 20psi. is that possible? I also had the SES light come on once and it flickered back off. another soft code. I'm going to check on it during lunch.

 

[85zoom]

20#'s of boost on a HotAir. No alky inj. Headgaskets????

 

[TURBOV6]

Xylene mixture with gas should be good around 100 octane.

 

[Turtle TR]

The stumbling has gone away. but I think it's still the MAF like Jackson suggested. Also...the car seems to be running rich. I think the o2 crapped out as well. it starts up fine, but it hesitates from a stop, acceling. pretty much reminisant of when I removed my air filter that one time. also, this morning, I took a diagnostics on the car and 22 and 34 werent present, though 44 came up. most likely a bad o2. hmm..time for a heated o2. I may put off changing the MAF because I'm going to convert to the 86/87 setup. but a temporary MAF replacement would be nice.

 

[Turtle TR]

Posted this on the Hot-Air section:

I checked for codes yesterday afternoon and found that the car was showing codes, 22 34 and 44. I fixed code 22, the voltage on the TPS was .04v now it’s .44v idle and 4.79 at WOT. I Unplugged the MAF sensor during diagnosing the problem and induced a code 34. 44 were found later in the afternoon. I have noticed the car had been running rich. The fumes are practically burning my nostril hair and my eyes. 44 could be a shorted or a dead O2. But after I reset the ECM, ran the car, and shorted the ALDL for codes. 44 wasn’t present. The car still smells rich. Also, on the freeway, I punched it to pass a slow moving bus, and shortly afterwards, the car started to stutter a little and back fire on the throttle. This was cruising at 55-60mph. Every time I’d be on the gas for a prolonged time, it starts to stutter a little then POP! Backfire. I think I read somewhere that a car can backfire if the car is running rich. Code 44 is not present, though I know by smell that the car is running rich. More than likely the O2 is bad. I’m going to purchase a heated O2. So because the O2 is bad, it causes the car to idle badly and roughly, as though it had a higher duration cam. Can a bad O2 cause the car to stutter just as I get on the gas from a stop? It’s been doing that. Also, can a bad MAF cause the car to run rich too?

 

[TURBOV6]

Any kind of trouble codes will cause you to run like crap! You mentioned a Heated 02? The one on it orig. is a single wire non-heated 02 sensor. If your not planning to run race gas probally better and cheaper to go with a non-heated 02. If you need on let me know and you can pick it up at Checker's on my Comercial account.

Another thing did you bypass the side breather? Also check the throddle blade for crud build up.

 

[84tt]

Hey Chris, I know how you feel.....my car is doing something similar to what yours is doing.....I borrowed a friends scan tool and I am trying to figure out what's going on......It seems like my MAF is bad too! First when I was trying to get my car running it would not rev-up.....the thing rev-ed up to 3500 then cut-off...turned out my computer's acting funny....Now the car is running smoother but stumbles when I try to give it some throttle....plus it running really rich......My MAF readings are too high so I think the maf is bad......O2 readings are quite high too, but I replaced the o2 sensor...
Does your scanner read the MAF output it might give you an idea of how much it is reading off....usually at idle i believe it should be around 8-12 or something...........Like my MAF readings is off and is telling the computer it is reading like 25 or something.....Oh well
another thing controlling fuel would be your MAP sensor or engine load.....this can also tell the computer to add more fuel....let me know what you find give me a call at 255-9617!!
Because my car is sounding like yours....only mine is really bad!!
KOA

 

[Turtle TR]

Man!! This sucks ass!!!! I think my MAF is still good, though I'm sending money order to this dude on the mainland who has, what I hope is a good MAF. I'm beginning to think that the O2 is shot. And it cant be my MAP because I dont have it hooked on. Though, I think I should have it back on...but I've been running without it for the longest time. The MAF code was induced by hand by disconnecting the plug. I also did the "tap" test on the MAF, and nothing. when I disconnected the MAF, it pretty much ran the same, small bogs and little misfires, though idle did smoothen out just a little, that's what's expected of a disconnected MAF. only 44 was induced at idle on morning. the SES ligh came on, knowing a code had been set. put the paper clips to it, there it was...code 44. Since reseting the ECM, no codes have been present. Not even the 44. But while driving on the freeway...fricken car backfires. 87Octane/Nesto was on the side of me and noticed that smoke had come out from the back as a result of backfire. I'm going to call Checkers tomorrow to see if the have any in stock. i'm also going to scan the car again and record what I find and report it back here on the forum to give a better picture of what's going on with the car.

 

[tazgn]

I think you are on the right track with the MAF sensor. If you unplug it and the idle doesn't get worse and more "broken up" I would say that's a good sign it's broke. I had the same problem a few years back. I tapped and tapped on the thing with NO changes. But I would unplug it and the idle didn't change at all. Replaced it, and PERFECTION!! I haven't read up the posts, but I assume you have some type of scan tool. That would probably help out a lot too. But my bad one seemed to read fine at idle, just a little different than what it read before it went bad (I think 3 instead of 7 on the scanmaster). Sorry I don't have one for you to try to check it out.

Derrick

 

[tazgn]

Also, I noticed this happened after porting the exhaust elbow and running over 20 psi. I would check to make sure all your intercooler hoses are on tight and you didn't blow a small hole out one of them on the bottom side. I've had that happen to me numerous times and you can't really tell unless you pull it off and bend it in strange ways to see the cracks. It could be you're sucking air in through holes in the hoses causing the MAF to not read what's really going into the engine. BTW, You check all the grounds (ESPECIALLY to the coil pack) and the two nuts that hold the front of the coil pack mounting plate are TIGHT. I had mine finger tight once and caused MANY different problems.

Just throwing out ideas. BTW anyone going to the track this weekend? I'm toying with the idea of making a couple "SOFT" runs just to try and get the felpro tuned right vice trying to do it on the back streets. I'm talking 92 octane and 15 psi boost max.

Derrick

 

[Turtle TR]

Thanks derrick, but I dont have an intercooler. I'm using an 86/87 elbow which bolts right on to the stock hot-air turbo. the only difference is that the puck arm is higher than the hot-airs version. I'm going to change out the elbow this weekend. I'm also sending in the money order to that dude on the mainland with the 85 MAF as soon as he replies to me with his mailing address. I'm also getting a GNX O2 sensor from Kirban's. I may also have to swap my Module and Coil pack. at the same time I'm going to buy the 86/87 ECM to swap out ECMs. I may have to touch base with Jay Carter or Joe Lubrant to cut me a chip to use the 86/87 ECM. I'll keep you guys tuned in.

 

[85zoom]

What's a stubling? Is that those little people that follow you around in the evening?

 

[Turtle TR]

I tried to get rid of them, but they just keep following me.