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Discussion Starter · #1 ·
I have been having issues with my 850, been to many mechanics and no one knows. <br>It is behaving as if there is water in the gas or it is not getting enough o2.<br>When you press the gas it may or may not go stuttering until it finally kicks in. It also gives out when driving, sudden loss of power, and then kicks in then out again continiously.. Hills are the worst it evens stalls out sometimes when you put the clutch in. It is also accompied by eratic idoling or very low, below 300rpm.<br>I have replaced the mass air flow, rpm sensor, main controller, checked o2 sensor, plugs cap and rotor, still no luck. <br>has anyone had this problem or have any suggestions?<br>thanks.<br>E
 

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Re: impossible problem (elizabeth)

It's too expensive to throw parts at these old cars. I suggest a dealer (Volvo of Charlottesville?) who is looking at these all day, everyday. Indy guys are good for a LOT, but it sounds like you have exhausted the indy option. <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/wink.gif" BORDER="0">
 

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Re: impossible problem (elizabeth)

I have been going through a similar problem as we speak and it seems to be coming from either the idle air control valve or throttle position switch, will know more tomorrow when I have the chance to check both. Are you getting any trouble codes?
 

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Re: impossible problem (elizabeth)

Sounds like it could be the fuel pump.<br>I have had a few on my lift like this one was the fuel pump and was a broken ground cable from the battery to the trans/sub frame.<br>Dont know if this is your problem but worth a look.<br>Try to put a fuel gauge on the rail and see if the fuel pressure drops off when your symptom occurs.
 

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2021 Inscription Recharge - 2021 Silverado LTZ 6.2L
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you have to check the codes, there should definitely be some. if so, like a fuel trim or such, I bet it's the front O2. if not, it's probably the pump which can be checked as previously mentioned. exhausting those options, a squirrely ground is probably last possibility as stated.
 

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Discussion Starter · #6 ·
Re: impossible problem (charles)

It has set a code only 3 times in the 7 months I have had this problem, for a rpm sensor, mass air and lately just the fuel trim, lean or rich. It rarely sets a code and hasn't for awhile. I had a gauge put on the fuel line and it seems to be getting enough pressure. I forgot to mention that it is completely ramdom, some times you can hardly budge it others it has no symptoms and I cannot seem to relate it to anything. If I lay off the gas when the problem occurs it sometimes helps, at least it doesn't sputter and fit so much.<br>Someone mentioned the ground, I am going to check that tonight. <br>Did you find anything out about the car you are working on?<br>
 

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Re: impossible problem (TurboMoose)

Mine turned out to be the throttle position sensor, pulled it apart and it was all filled with debris (dirt etc), blew it all out re-connected and it has not happenned since.
 

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Does it do it on a timed interval? <p>The reason I ask is, I had a stalling problem exactly 10 seconds after startup on my gf's 850. I went through EVERYTHING. Turned out the wiring for the AC compressor relay had melted together and would short out when the ECU would cycle over the AC compressor. When it did, it would stall out the motor.<p>When in doubt, try pulling some fuses. No joke. It was the only way we found the problem after numerous dealer visits
 
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