Dead Shark HELP!!!! Problem found.. fuel pump...95%?
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From: Stockton, CA
Dead Shark HELP!!!! Problem found.. fuel pump...95%?
Okay my 88 auto has been moody lately...I noticed at the track when pointed downhill it would loose power briefly, then resume with no problems...it also did it when hitting sharp bumps on the freeway....so I changed the LH relay hoping it would help?
Today on my way to Taco Tuesday it died on the freeway on-ramp right by house.....I change the fuel pump relay too.....it will start..idle for a couple seconds tops...then stall and not start again for a few minutes...then it does the exact same thing...start....give it some gas and it dies instantly.....
I have it towed home....call Bill.....there is voltage between pins 30-87 on the fuel pump and LH brain.....I jumper the fuel pump, hear it running and start the car...it does exactly what it did before...and the pump stops running for a few minutes...
I'm thinking its the LH brain...since the fuel pump cuts out even when jumpered....next step will be to pull the brain and try it in Gerry's to see if it works (most likely won't)
HELP...
Today on my way to Taco Tuesday it died on the freeway on-ramp right by house.....I change the fuel pump relay too.....it will start..idle for a couple seconds tops...then stall and not start again for a few minutes...then it does the exact same thing...start....give it some gas and it dies instantly.....
I have it towed home....call Bill.....there is voltage between pins 30-87 on the fuel pump and LH brain.....I jumper the fuel pump, hear it running and start the car...it does exactly what it did before...and the pump stops running for a few minutes...
I'm thinking its the LH brain...since the fuel pump cuts out even when jumpered....next step will be to pull the brain and try it in Gerry's to see if it works (most likely won't)
HELP...
Last edited by IcemanG17; Jun 9, 2007 at 08:20 PM.
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From: Stockton, CA
If the fuel pump was dead....why would it run briefly then die after the car starts? It seems wierd....Since the relay is jumpered in the LH can't stop the pump right? Then why would the jumper not work? Tomorrow I will make a new jumper to make sure its good...& try again.....
I just changed the fuel pressure check valve BEFORE all these problems started....maybe the wires on the pump are loose? Or the pump is dying?
I just changed the fuel pressure check valve BEFORE all these problems started....maybe the wires on the pump are loose? Or the pump is dying?
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From: Stockton, CA
UPDATE.....
Assuming my 1/2 assed jumper didn't work...I soldered up a new one...then I checked the resistance of it...it came back .1 ohms...so its fine....made sure to get the jumper in there really good....fuel pump started running....CAR STARTS and idled fine.....so it was the fuel pump relay...I did follow Wally's advice and twist fuse 42 just a bit to make sure it was connecting... I'll mess with the relays tomorrow, sounds like soem dielectric grease to improve connections is in order! So I payed $60 for a tow when I should have been able to fix it right there on the side of the road....DAMM DAMM DAMM...No tacos for the SSS today!
Assuming my 1/2 assed jumper didn't work...I soldered up a new one...then I checked the resistance of it...it came back .1 ohms...so its fine....made sure to get the jumper in there really good....fuel pump started running....CAR STARTS and idled fine.....so it was the fuel pump relay...I did follow Wally's advice and twist fuse 42 just a bit to make sure it was connecting... I'll mess with the relays tomorrow, sounds like soem dielectric grease to improve connections is in order! So I payed $60 for a tow when I should have been able to fix it right there on the side of the road....DAMM DAMM DAMM...No tacos for the SSS today!
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Brian--
Contrary to some old wive's myth tales, dielectric grease does NOT improve connections. In fact, if it's in the connection it will make it worse. Most of the connections in the CE panel are 'self wiping', so that removing and replacing a relay or fuse will scrub off oxidadtion a bit, usually enough to get a good connection again. A few good pull-and-replace cycles will often give you like-new contact resistance. Since the CE panel is dry, there's really no need for grease on the connections in there at all. If you must, use one of the spray contact preservatives, but only after the connections are firmly established.
Just about the only valid use for dielectric grease on the car is for spark plug boots, where there's a risk of moisture allowing a spark to track to ground. The grease keeps the water and other conductive crud from sucking up inside the boots. For almost all other low-voltage connections, use Vaseline. That would include the battery terminals after the clamps are secured, the jump-start terminal under the bonnet, maybe the connections on teh starter. Again, grease only after the connection is mechanically and electrically secure.
Your post did remind me to stock up on a few 53 relays, and maybe make a nive 12-gauge jumper with a fuseholder in the middle. A man-sized jumper that won't glow red under load. After reading your note, I think it will be soldered and heat-shrinked too; No cheezy crimp connections for this one...
Hope you got away for a ding on your AAA card. Cooooda been a lot worse, a lot further away (like half way between Westminster and Stockton on a holiday weekend...), with only Bubba's Garage as a repair station. Gomer certified Bubba as a good makanik, so you know you'd be in good hands.
Contrary to some old wive's myth tales, dielectric grease does NOT improve connections. In fact, if it's in the connection it will make it worse. Most of the connections in the CE panel are 'self wiping', so that removing and replacing a relay or fuse will scrub off oxidadtion a bit, usually enough to get a good connection again. A few good pull-and-replace cycles will often give you like-new contact resistance. Since the CE panel is dry, there's really no need for grease on the connections in there at all. If you must, use one of the spray contact preservatives, but only after the connections are firmly established.
Just about the only valid use for dielectric grease on the car is for spark plug boots, where there's a risk of moisture allowing a spark to track to ground. The grease keeps the water and other conductive crud from sucking up inside the boots. For almost all other low-voltage connections, use Vaseline. That would include the battery terminals after the clamps are secured, the jump-start terminal under the bonnet, maybe the connections on teh starter. Again, grease only after the connection is mechanically and electrically secure.
Your post did remind me to stock up on a few 53 relays, and maybe make a nive 12-gauge jumper with a fuseholder in the middle. A man-sized jumper that won't glow red under load. After reading your note, I think it will be soldered and heat-shrinked too; No cheezy crimp connections for this one...
Hope you got away for a ding on your AAA card. Cooooda been a lot worse, a lot further away (like half way between Westminster and Stockton on a holiday weekend...), with only Bubba's Garage as a repair station. Gomer certified Bubba as a good makanik, so you know you'd be in good hands.
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From: Stockton, CA
I used the defroster relay in the fuel pump spot.......it runs fine..........it figures that my "extra" relay I had in the glovebox was broken.....but dropping it on the garage floor generally isn't good (but it was in the box)..... it would have been much easier if that was a simple fix.....oh well
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From: Stockton, CA
Since there are 8 253B relays on the board...they are easy to find.....another bummer of the "roman numeral" board is I thought I replaced the HVAC blower relay, since it was acting funny....turns out I replaced the Defroster relay instead......nice one......why didn't I think of my relay stickers SOONER....we'll see how good sharky runs tomorrow!!
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From: Southern Alberta, Canada
I replaced all 8 253B relays early this Spring as part of my PM.
I then tore apart one of them making a jumper from 2 of the relay legs, 50mm of wire, some solder and shrink tube.
Good you found the issue, easy to replace and cheap.
I then tore apart one of them making a jumper from 2 of the relay legs, 50mm of wire, some solder and shrink tube.
Good you found the issue, easy to replace and cheap.
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From: Anaheim California
The new chant is" RELAY, RELAY, RELAY ...FUSE ! " and when in need simply borrow the horn relay to replace the fuel pump relay on the LH cars same #53 relay. And if you are dead in the water and jumper the fuel pump relay and the pump does not run ...check the fuse ! The fuses are after the relay...
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From: Boulder Creek, CA
Brian, if Karl Malden had a 928 he would have been peddling AAA cards with the line "Don't leave home without it". 
$85/year for "Plus" membership, 400 miles free towing...(4x 100mi/incident) tough act to follow.
$85/year for "Plus" membership, 400 miles free towing...(4x 100mi/incident) tough act to follow.
See you at the lake. 
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From: Stockton, CA
last night after changing the relay with the defroster relay it ran fine......so I turned it around and put it back in the garage the normal way.....
So today I go out and start it........it starts fine.....idles fine for maybe 10 seconds......then DIES...... & doesn't start again..................................
Of course now its on the "tight" side of the garage......so it will be a total bitch to get to the fuse panel in the 1st place............now I'm thinking it might be the LH again............
What do I do now? The relays are fine........or else it wouldn't start.....I was thinking the relays or fuse aren't making contact...but it wouldn't even start if that was the case......its gotta be the LH....what else could it be?
So today I go out and start it........it starts fine.....idles fine for maybe 10 seconds......then DIES...... & doesn't start again..................................
Of course now its on the "tight" side of the garage......so it will be a total bitch to get to the fuse panel in the 1st place............now I'm thinking it might be the LH again............
What do I do now? The relays are fine........or else it wouldn't start.....I was thinking the relays or fuse aren't making contact...but it wouldn't even start if that was the case......its gotta be the LH....what else could it be?