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Discussion Starter #1
At pretty much the same time my 1991 2.6 began having cold start problems and the auxiliary fans stopped coming on when the AC was turned on. I didn't notice the fan issue right away so am not certain about the coincident timing. Could both be symptoms of a fuel pump relay issue or are they totally unrelated problems?
 

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i dont think its related for the fans sounds like a bad relay. as for the cold start i would start with the ovp then i would check the CSV. when was the last full tune-up on the car?
 

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Discussion Starter #3
Complete tune up about 18 months, spark plugs recently. Also replaced OVP last year. CSV's are expensive to replace. Is there an easy way to check? Thanks.
 

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get a used CSV at your local picapart, shouldn't cost much and the odds are that it will work fine. if your symptoms remain after installing the replacement, the problem is elsewhere.
 

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Discussion Starter #6
I got a used cold start valve from ebay but it has a blue color # 0 280 170 412. My old one is more of a yellow color # 0 000 714 737. I should have taken the old one off first to get a better look at it. Can it still be made to work or should I find another one?
 

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if the ebay seller will confirm that what he delivered to you is for the 2.6, and the ebay unit is physically identical to what your have (including connector), then it will probably work fine. at least it will be worth the effort to try it. if your symptoms remain, i'd switch back to the original and look elsewhere.

btw, the aux fan and clutch fan should both engage when the a/c pressure at the output side of the condenser (mounted in front of the radiator) is above some limit. a pressure switch drives the aux relay which drives the aux fan and clutch fan through separate contacts. when my aux relay died, then clutch fan engaged, but the aux fan did not. the aux relay in located in the fuse box, can be ordered online, and easy to replace. the clutch fan will also be engaged by an engine temp switch, and the aux fan will be started by another engine temp switch which has a higher trip point.
 
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