Bad Fuel Pump?

[346sfi]

Okay, is this “too obvious”? Or do I in fact need a new fuel pump?

My 1988 convertible has been having a hot start problem for several seasons (I live in Michigan so we have “Corvette seasons” when we can drive our cars!)

The injector resistance readings check out fine. I was told by a tech some time ago that likely the fuel pressure was not building up enough to “clear the fuel vapors out” of the system without several seconds of running the starter. It always started fine after sitting overnight but not if it sat for anywhere from 15 minutes to a few hours.

Toward the end of last season and after bringing it out of storage this year I began to notice that it did not fire up as quickly when cold. Last weekend, I went to start it cold and did not hear the fuel pump when I turned the key. It cranked strong but would not fire up. I tried two more times and it finally started, but code 54 “Low Fuel Pump Voltage” was set.

If not the fuel pump itself what else could be the problem?

Thanks.

[c4c5specialist]

Hi there,
It would be suggested to also obtain a fuel pump relay.
That relay is monitored by the ECM for voltage to it.
These relays have been known at times to create problems.
Then, reevaluate the fuel pump.
Allthebest, c4c5

[346sfi]

Originally Posted by c4c5specialist

Hi there,
It would be suggested to also obtain a fuel pump relay.
That relay is monitored by the ECM for voltage to it.
These relays have been known at times to create problems.
Then, reevaluate the fuel pump.
Allthebest, c4c5

Thanks. Uh - where will I find the fuel pump relay in the car? Also is it the same relay as the MAF anf MAF burn off relays? I ask because I have some of those as spares already.

Thanks for all that you do for this forum and its members and your willingness to share your knowledge.

George

[c4c5specialist]

HI there,
The relay should be in the center of the firewall, and its part number 14089936.
Allthebest, c4c5

[ChuckG]

I'm having the same issue with my '85 since the new MAF. Do I have the same relay?

[ChuckG]

I'm having the same issue with my '85 since the new MAF. Do I have the same relay?

[346sfi]

Originally Posted by ChuckG

I'm having the same issue with my '85 since the new MAF. Do I have the same relay?

Yes the same relay is used for many applications on the C4 - MAF sensor and MAF Burn off; Fuel Pump; Cooling Fan, etc.

Is this the same Chuck that was at our club "work day" and picnic last Saturday?

George

[ChuckG]

Thanks. Off to get more relays... Is the C4 just a repository for relays? Seems so.

Sorry, different Chuck

[346sfi]

Originally Posted by ChuckG

Thanks. Off to get more relays... Is the C4 just a repository for relays? Seems so.

Sorry, different Chuck

Okay, then if you are another Chuck, but do live in Ann Arbor, let me invite you to check out our club. We are based in Western Wayne County. I am a founding member and past president and currently chairman of the juding at our annual all Corvette show coming up in July, so can answer any questions you may have.

Details are at http://corvettelegends.net and http://corvettesatthesummit.com

If you do come to our cruise nights or show stop and introduce yourself to George - I'll have either my 2003 Gray Coupe or my wife's 1988 Dark Red Metallic Convertible - or both.

All the best.

[ChuckG]

Sounds like a plan!

Will definitely check out the cruise nights. Like to find my '85 a good home. Sold my Shelby and if I sell this, well on my way to a Blue Devil....