Help! 89 Won't start when warm. Lets try again plz...

[muddywaters]

Their should be a shield over the filter that has to come off first. If the car was sitting over night and wasn't started, with injectors that are leaking down ,you probably won't have pressure in the fuel sys.,I didn't, but it would be a good idea to check that at the schreader valve, otherwise you'll get some squirt gun action when you undo the filter, have a rag ready and watch the drop light. My 88 did the exact same thing your 89 is doing, started cold perfectly, ran good, fuel milage sucked, took forever to start when hot. I think it a common problem with the older FI Vettes. Mine never ran better, Good luck, Go Pens.......................Joe P.S. There's a lot of aftermarket CRAP out there, spend a couple of bucks more and go with a better AC filter.

 

[TedC]

Even when my 1988 had leaking injectors, it always maintained a fuel pressure around 40 when running. Similar pressures on my 1989. Low 30s is not going to give you optimal performance.

 

[vetteoz]

If the car was sitting over night and wasn't started, with injectors that are leaking down ,you probably won't have pressure in the fuel sys.

Change filter with minimum fuel in tank because it will siphon out on account of tank being higher than filter even after you have relieved pressure .
Easiest way is to remove supply line at tank under filler cap , you will only lose what fuel that is in the line and have all day to change filter if you have not done one before.

 

[TedC]

Vetteoz, I've changed several fuel filters on diffrent model C4s and never had the siphoning effect (just lucky ?). Just changed mine with a full tank. I release the fuel pressure on the rail and make sure the converter has cooled down. The fuel filter is very close to the converter. Sure wish they would include new o-rings with these filters. I stopped buying AC fuel filters when the last one said made in China.

 

[muddywaters]

I had no siphoning problems either, just a little dribble. As far as filters go ,what isn't made in China these days. The no name filters are made in Bangladesh. I've been hearing that Wix is the way to go, next filter change I'll go that route....If I can find them.....

 

[TedC]

The fuel filters at NAPA had made in the USA or Mexico. I had a similar issue with an oil pressure sensor last year. The Delco part was made overseas (black in color) just like the ones at PB and AZ. The NAPA part was gray and stamped made in the USA. I purchased the AC and the NAPA sensor and tested them. NAPA part provided more consistent readings. How times have changed.