89 S4 Stumbling / No Power ( Problem Solved )
#1
Racer
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1st time on the road with this car, its stumbling and lacks any power it does get up to highway speed.
I've replaced the plugs, cleaned caps-rotors, new ones on order, checked spark with inductive timing light,
checked the vacuum at idle it does seem on the low side ( 16inches )
no obvious vacuum leaks, checked fuel dampers no gas in the vacuum lines,
added textron and Marvel mystery oil to gas tank.
I pulled off the air cleaner box and found the MAF seal was just hanging on could this be my problem ?
I've replaced the plugs, cleaned caps-rotors, new ones on order, checked spark with inductive timing light,
checked the vacuum at idle it does seem on the low side ( 16inches )
no obvious vacuum leaks, checked fuel dampers no gas in the vacuum lines,
added textron and Marvel mystery oil to gas tank.
I pulled off the air cleaner box and found the MAF seal was just hanging on could this be my problem ?
Last edited by pjg; 12-10-2011 at 01:37 PM. Reason: problem solved
#2
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Doubtful that is the primary cause of your low power. Have you checked fuel pressure? Does it run worse when the MAF connector is unplugged? Low power only when cold or even when hot? If only when low check the resistance of both channels on the Temp II sensor. Check coil wires, primary and secondary, for corrosion and make sure coil grounds are tight and clean. If you run it in a dark garage do you have fireflies from the plug wires arcing?
Mike
Mike
Mike
Mike
#4
Three Wheelin'
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If you have one (and I believe you might) check the in-tank fuel pump. If it's typically got the broken hose, replace the pump with an in-tank filter from 928's R Us and life will be good.....although you might have a bad main pump too now because of it. Been there, done that.
#5
Racer
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#9
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Do as Hilton sugggests and check that clear relay. If either the red or green LED are lit, do NOT drive the car. (danger of snapping the drive shaft in the torque tube)
#10
Racer
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#11
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The Beru wires are complete with dist. cap ends, new resistor ended stingers for attaching to the plugs, and fully assembled with all new wire loom clips/holders properly positioned. Plus they last about 20 years. Do a search hereabouts and you will see the quality and precision details that make the price seem more reasonable.
Mike
Mike
#12
Racer
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Sanity check
Checked compression all are in the 180 to 190 range, plugs are brand new so its hard to tell but 2 and 8 don't look like they are firing, thats on the drivers side, the arcing wires were on the passenger side. new caps rotors are on the way already, will order the Beru plug wires today.
Checked compression all are in the 180 to 190 range, plugs are brand new so its hard to tell but 2 and 8 don't look like they are firing, thats on the drivers side, the arcing wires were on the passenger side. new caps rotors are on the way already, will order the Beru plug wires today.
#15
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Beru full factory wire set $335 at 928sRus.
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."![thumbsup](https://rennlist.com/forums/graemlins/bigok.gif)
![](https://cdn.shopify.com/s/files/1/1694/8685/files/928sRus_rennlist.png?v=1621798567)
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
![thumbsup](https://rennlist.com/forums/graemlins/bigok.gif)
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
![thumbsup](https://rennlist.com/forums/graemlins/bigok.gif)