Had the GN out today to a show and it ran perfect on the way over. On the way home while under part throttle (about 1/4) the car would stumble like starving for fuel for a second or two. Enough for the check engine to flash on a split second. It did this 3 or 4 times on a 10 mile trip. I made it back to the garage and while idling waiting for the garage door to open it stalled. At this point I figured it was fuel pump related. (I have a 304 hot wired with about 2000 miles on it) I opened the hood to check the fuel presure gauge expecting it to be on zero .. but it was not.. Hmmm don't seem to be fuel pump related after all. The ignition module is 1500 miles new as is the crank sensor. Cam sensor is original.(60k miles) MAF is NOS with about 2000 miles on it.. Someone following me as it stumbles said it blew black smoke.. Whats everyone think??
need troubleshooting help here guys
- Thread starter FlyinGN
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MeanBuicks
Scaring the neighbors!
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I had similar symptoms at one point years ago. It happened on and off for about a week until one time, coming home from work, it stalled for good. I threw my spare ECM/stock chip on there to get home and it turned out that the chip went belly up.
Check the MAF
Roll the back of a screw driver over the MAF while it is running if the idle changes or kills the engine it means your maf is going bad.It sounds like a problem i once had and it was my MAF.Hope this might help if you are still using the stock MAF sensor
Roll the back of a screw driver over the MAF while it is running if the idle changes or kills the engine it means your maf is going bad.It sounds like a problem i once had and it was my MAF.Hope this might help if you are still using the stock MAF sensor
TR Custom Parts
Mark Hueffman - Owner
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Betting on the MAF!
salvageV6
Daily Driver
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- May 25, 2001
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Bad connection on the chip or ECM connectors.
I'd try a Caspers tester as well.
Any codes stored?
I'd try a Caspers tester as well.
Any codes stored?
salvageV6
Daily Driver
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I'd check the module connector as well.
Old wiggle test on the ends and contact cleaner should you have some.
Make sure it's seated properly and the bolt is tight for it.
Old wiggle test on the ends and contact cleaner should you have some.
Make sure it's seated properly and the bolt is tight for it.
charleslong
Member
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- Dec 14, 2001
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- 620
I had similar problems that you described, and it turned out that some how my ecm got wet where the connector hooks up to it. The water was sitting in and around the pins causing shorts.
Charles
Charles
Any luck finding anything yet? I've also had problems with vac lines coming loose. The one to the fuel canister came off before and gave similar problems, although not quite as bad and didn't blow black smoke. I had a bad MAF but didn't notice problems at low rpms and idle, only when I got on it.
Does your chip have open or closed loop idle? May help narrow it down.
Does your chip have open or closed loop idle? May help narrow it down.
Its a show car so I will not change the maf till I get time again.. maybe some time this week after work..
The chip is a closed loop Red armstrong 93 for 50 lb injectors. Its been fine for a while so Its not a bad chip..
Charles. The car never sees water
Ill check bith the chip legs and the maf. I have a new Granatelli adj maf in front of me waiting to go on..
The chip is a closed loop Red armstrong 93 for 50 lb injectors. Its been fine for a while so Its not a bad chip..
Charles. The car never sees water
Ill check bith the chip legs and the maf. I have a new Granatelli adj maf in front of me waiting to go on..
Had the same sort of problem about a year ago. Checked everything that could have been a problem without any luck. Turns out I had got some bad gas. Drained the gas from the tank and sure enough, had some water mixed in with the fuel. Filled it up with some good gas and the problem went away.
Sounds too simple, but worth a check if everything else checks out OK
Paul
86 GN
66 Riv GS
Sounds too simple, but worth a check if everything else checks out OK
Paul
86 GN
66 Riv GS
wickedmotorhead
SQWURLY
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- Jul 5, 2004
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- 80
I have the same problem. So I took out my ECM and tapped on it while it was running and it started to do the stumble. Tapped on it again and it ran fine. I would put my money on your ECM.
charleslong
Member
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Originally posted by FlyinGN
Its a show car so I will not change the maf till I get time again.. maybe some time this week after work..
The chip is a closed loop Red armstrong 93 for 50 lb injectors. Its been fine for a while so Its not a bad chip..
Charles. The car never sees water
Ill check bith the chip legs and the maf. I have a new Granatelli adj maf in front of me waiting to go on..
I hear you, I had that problem after washing my car one day. I havent had that problem since.
UPDATE!!!!
Changed out the maf and went to start.. crank crank crank.. nothing..
Changed back to the other maf incase ther replacement was bad. .. nothing..
Damn.. I check spark. Yup. And also have fuel pressure.. Unplugged the cam sensor and still nothing..
Pulled the ECM and checked the connector.. its fine.. as are the chip legs.. does this sound like an ECM gone bad?? I get a flashing voltmeter light when I turn key on.. odd.. What do you guys think??
Changed out the maf and went to start.. crank crank crank.. nothing..
Changed back to the other maf incase ther replacement was bad. .. nothing..
Damn.. I check spark. Yup. And also have fuel pressure.. Unplugged the cam sensor and still nothing..
Pulled the ECM and checked the connector.. its fine.. as are the chip legs.. does this sound like an ECM gone bad?? I get a flashing voltmeter light when I turn key on.. odd.. What do you guys think??
Dan Thompson
New Member
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- May 25, 2001
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How is the crank sensor?
Frank, do you get a check engine light at key on?
One thing I had, because I used to pull my ecm out so often, the orange wire, I think A1 or whatever, plled out of the ECM plug. When this woulod hapen, of course a no start. Was intermittent. Found it one day swapping chips when I saw the silver of the connector sticking out of the plug. I kinda knew where to look because when it wouldnt start, I had no check engine light.
Just a thought
One thing I had, because I used to pull my ecm out so often, the orange wire, I think A1 or whatever, plled out of the ECM plug. When this woulod hapen, of course a no start. Was intermittent. Found it one day swapping chips when I saw the silver of the connector sticking out of the plug. I kinda knew where to look because when it wouldnt start, I had no check engine light.
Just a thought
