Tonight's 928 quiz- Solve the mystery rough running problem
#1
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Tonight's 928 quiz- Solve the mystery rough running problem
OK,
Let me start by saying I've already solved the problem, just wanted to see who would be first to solve it from the clues I give you:
Background:
My car (my DD) has been running really well for at least 6 months now. Idle has been rock steady 750 since I took care of all the vacuum leaks in November. Always starts, no problem with the engine at all since then (clutch doesn't count as 'engine' trouble, right?).
Symptoms:
I get in it after I get off the train and start it up, no problem. I pull out and notice it's idling a little low, like 500, but no other issues. I figure it will warm up and creep up.
I stop at a light and it does go up to 750 nice and smooth, OK.
Next light I stop, then go to pull out and I lose power at about 1200 rpms in 1st, before I was ready to shift. I clutch, check the gauges, no problems showing. I give it gas, again 1200-1400 and it cuts out, back down to 500 rpms.
Now I'm worried, so I pull over and leave it idling. It's sitting at 750, nice and smooth, but if I step on the gas, it goes up to 1200 and then divebombs back down to 750 and smooths out. Guages show no warning lights, temp ok, gas guage above the empty line, but below 2/4 of a tank, oil pressure 4-5 bar.
OK, I leave it running for a few minutes then it dies. I start it up, it idles for a few minutes then dies again. I start it up, it runs for 10 seconds then dies again.
You make the call. What's the problem?
Let me start by saying I've already solved the problem, just wanted to see who would be first to solve it from the clues I give you:
Background:
My car (my DD) has been running really well for at least 6 months now. Idle has been rock steady 750 since I took care of all the vacuum leaks in November. Always starts, no problem with the engine at all since then (clutch doesn't count as 'engine' trouble, right?).
Symptoms:
I get in it after I get off the train and start it up, no problem. I pull out and notice it's idling a little low, like 500, but no other issues. I figure it will warm up and creep up.
I stop at a light and it does go up to 750 nice and smooth, OK.
Next light I stop, then go to pull out and I lose power at about 1200 rpms in 1st, before I was ready to shift. I clutch, check the gauges, no problems showing. I give it gas, again 1200-1400 and it cuts out, back down to 500 rpms.
Now I'm worried, so I pull over and leave it idling. It's sitting at 750, nice and smooth, but if I step on the gas, it goes up to 1200 and then divebombs back down to 750 and smooths out. Guages show no warning lights, temp ok, gas guage above the empty line, but below 2/4 of a tank, oil pressure 4-5 bar.
OK, I leave it running for a few minutes then it dies. I start it up, it idles for a few minutes then dies again. I start it up, it runs for 10 seconds then dies again.
You make the call. What's the problem?
#7
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Smell a lot of gas? Pull a few spark plugs (at least one from each rotor). Is a plug wet or the cylinder full of gas? If it's not flooding half the cylinders...
If it is flooding, check the ignition system. Rotors, coils, coil wires, ignition modules...
Originally Posted by the flyin' scotsman
MAF?
Originally Posted by macreel
Temp II,
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#8
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Fuel filter would be my best generic guess but 928's never fail like that as other cars do. So ... I'd say, has to be a disconnected thing somewhere. Best guess .... MAF disconnected.
#9
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We have a winner!!!
And the winner is:
Rod Kubis. This is the first time I'd let the gauge go that low and apparently the reserve section is below the bottom of my range. My guage read at least 1/8" above the bottom line (which is above the reserve line) but apparently that means EMPTY in my car.
I called my wife who brought the gas can and I was on the road inside an hour.
Originally Posted by 69gaugeman
out of gas?
Rod Kubis. This is the first time I'd let the gauge go that low and apparently the reserve section is below the bottom of my range. My guage read at least 1/8" above the bottom line (which is above the reserve line) but apparently that means EMPTY in my car.
I called my wife who brought the gas can and I was on the road inside an hour.
#12
Former Vendor
Damn. I was going to guess a bad muffler bearing. Wrong again.
gb
gb
#13
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Can we have a do-over? I want to change my vote. I didn't read the whole thing. I didn't understand the question. My dog distracted me. I wasn't completely awake. I'm on pain medication. It's my patents' fault for never buying me that shiny Western Flyer. Aliens probed me and gave me a lobotomy. There was something in my eye. DR has a mind-control chip in my brain .....
Btw, that bit of "work" would have cost you several hundreds at an "autohaus". I've pushed the envelope on my gasoline level, and come within what should be a few milliletres of the end of the line. Didn't your gas warning light tell you that something might be afoot?
Btw, that bit of "work" would have cost you several hundreds at an "autohaus". I've pushed the envelope on my gasoline level, and come within what should be a few milliletres of the end of the line. Didn't your gas warning light tell you that something might be afoot?
#14
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Originally Posted by heinrich
Can we have a do-over? I want to change my vote. I didn't read the whole thing. I didn't understand the question. My dog distracted me. I wasn't completely awake. I'm on pain medication. It's my patents' fault for never buying me that shiny Western Flyer. Aliens probed me and gave me a lobotomy. There was something in my eye. DR has a mind-control chip in my brain .....
Now we know why you are the way you are H..........with all of the above issues; wow (j/k).
Hopefully you get better soon
#15
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Originally Posted by Heinrich
Didn't your gas warning light tell you that something might be afoot?