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Losing Power on 3 and 4 Cyls

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98 OBW w/ DOHC 2.5L....just finished head gaskets, seals, valve job, timing belt., etc.'

 

Car drives fine for about 100 miles ...then drops 3 and 4....pulling fuse #14 (ECU backup) restores power for another 100 miles.

 

What can cause engine to lose cyls 3 and 4 like this....

 

Have replaced coil and ignitor with known good units...even replaced ECU..

 

Warren C.

Check the ignitor .. they can cause some very bizzare issues. Are you sure your loosing spark? The coil is of waste design, meaning that two cylinders fire at the same time, but only one is under compression.

 

 

nipper

At about 100 miles after clearing the codes, we get P1507 as a code. THis translates to "Idle Air Control underspeed error" or somesuch. Autozone pulled the codes (actually, they lent me the tool so I could), and looked up the resulting code (which came close to what was displayed on the screen). I suspect a dirty IAC valve, and perhaps VSS2. Now I do not loose the Cruise control when I get the CEL, so I suspect this is an intermitant problem if it actually is the VSS. I cleared the codes this AM, and got a CEL within 30 miles. . . Perhaps it is getting worse. . .but I did not loose power like I did the earlier times. . .

 

I'm also having an issue with the hydraulic clutch system. The clutch slave does not seem to hold the preload well (and I end up having to push the pedal almost to the floor to get any clutch action at all)

time for a slave cylinder and or clutch mater cylinder. At that age i woud replace them both. You know if you replace one the other one is going to go.

 

 

nipper

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