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Intermittent rough Idle, engine shake and gas smell after cold start s


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Do I need to call 911 or what ? Yesterday I was bound for Charlotte, N.C. from Columbia, S.C. in my MY 99 Carrera 6 spd and my ride began to sputter like crazy so thinking that it may just be a gremlin hanging out temporarily, I rode up my street and out of the development for @ 1/2 mile tops. The car continued to hesitate at times with the gas pedal feeling like jello. Also I had some backfire along the way. Turned around and parked in my garage, turned the engine off and waited @ 3 mins. Started the car and there was some residual hesitation at first but whatever had been plaguing the car had gone. Drove down the street and everything was normal as if this episode had never happened (I drove my wife's car to Charlotte :). This morning I started the car and the same thing, crazy sputtering, with some surges and strong small of gasoline. The engine light began flashing at one point (This is not good). I'm accustomed to the light being on constantly due to some emission components that i'm planning to have my indy replace soon(air change over valve and SAI valve-notorious P0410 and P1411). I had all new Beru spark plugs replaced last year @ this time along with 2 Beru Coil packs (I don't know how long the remaining four have been in the car), Sounds like, tastes like, looks like what ? I'm banking on the remaining Coils and possibly the fuel filter combination. Any thoughts guys. The engine shake resembled someone going through delirium tremens. Both Pre Cat O2 sensors were replaced @ this time last year also. I replaced the fuel filler vent valve, operating purge valve and the vapor canister @ 12/2015. ????????????????????????? Any insight on this would be greatly appreciated or just point me in the direction of a previous post that answers the question.         Thanks

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Do I need to call 911 or what ? Yesterday I was bound for Charlotte, N.C. from Columbia, S.C. in my MY 99 Carrera 6 spd and my ride began to sputter like crazy so thinking that it may just be a gremlin hanging out temporarily, I rode up my street and out of the development for @ 1/2 mile tops. The car continued to hesitate at times with the gas pedal feeling like jello. Also I had some backfire along the way. Turned around and parked in my garage, turned the engine off and waited @ 3 mins. Started the car and there was some residual hesitation at first but whatever had been plaguing the car had gone. Drove down the street and everything was normal as if this episode had never happened (I drove my wife's car to Charlotte :). This morning I started the car and the same thing, crazy sputtering, with some surges and strong small of gasoline. The engine light began flashing at one point (This is not good). I'm accustomed to the light being on constantly due to some emission components that i'm planning to have my indy replace soon(air change over valve and SAI valve-notorious P0410 and P1411). I had all new Beru spark plugs replaced last year @ this time along with 2 Beru Coil packs (I don't know how long the remaining four have been in the car), Sounds like, tastes like, looks like what ? I'm banking on the remaining Coils and possibly the fuel filter combination. Any thoughts guys. The engine shake resembled someone going through delirium tremens. Both Pre Cat O2 sensors were replaced @ this time last year also. I replaced the fuel filler vent valve, operating purge valve and the vapor canister @ 12/2015. ????????????????????????? Any insight on this would be greatly appreciated or just point me in the direction of a previous post that answers the question.         Thanks

 

Sounds like a bad misfire, but without a scan and the codes triggering the MIL, anything would be a guess.

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A misfire (no spark) causes unburnt fuel to enter the exhaust tract where it's ignited by heat and results in a backfire.   Those were the days in the 60's when you could drive along and turn the ignition key off and then on and cause backfire.  All the kids used to do it.  

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So, you've been driving around with a CEL, and now it's gotten worse? Hummmmm. Need codes. My guess is your MAF is toast. Disconnect, and see if it runs better. Remote guess is a tank of bad fuel.

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  • 2 weeks later...

Well, a week has gone by and I'm grounded temporarily. I've ordered a  new 6 pack of ignition coils (I know, I haven't performed a diagnostic) and also plugs just in case the current ones have been fouled. I have read through the various post and all of the symptoms point at the coils or the injectors (I'm not necessarily believing the latter).  When I look back at my car's characteristics for the last 2 months, I realize now that there was a degree of reduced performance but we can get somewhat immuned to it over time, especially if we're too busy having a "Kool Aid" smile seared into the soft palate of our skull. The parts are due to arrive this Friday and the Tow truck next Monday. All will be well. Anyone know of a good  diagnostic scanner for sale on the forum or of anyone looking to part with one ? ie. icarsoft 80 etc.

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I also wanted to say thanks for all of your inputs. To 987S: No the car has had a cell on intermittently since I purchased it, diagnosed it through Autozone and Firestone and the notorious P01411 and P0410 came up . The last time autozone did a scan, the picture actually came up on the monitor and it was the SAI air change over valve that was the culprit so I've purchased both the SAI air change over valve and the air injection valve that is separated from the former by a hose. Again the car was showing signs of decreased performance in very small and barely noticeable increments. You do have a point however about the MAF sensor needing replacement.(It's all about the Benjamins these days y'know ?

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  • 2 months later...

All is well now. It turned out to be the remaining coils so I replaced all of them along with the spark plugs just in case the latter were fouled. I purchased replacement coils and not the Beru coils which are more costly than their generic counterparts and notice a slight difference in the car's performance but not in a significant way.

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