Removing Distributor
Mother Trucker
Joined: Jul 2009
Posts: 887
Likes: 8
From: Roggen, Co
Find a way to check your fuel pressure like he said...good first place to start. If your not smelling gas then its a good chance that what it is. How many miles are on the truck? My gramps has an 03 chev pickup, he just bought it, had it sittin in the shop, he fired it up, put it in 4x4 (just for the hell of it to make sure it worked) and the motor died. Ended up being the fuel pump....65000 miles. Pumps can go at anytime.
Hi-Rev Motorsports
Joined: Aug 2009
Posts: 4,898
Likes: 65
From: Northern Indiana
true and sometimes the problem can be the additives....there is a reason Dealers dont clean injectors by dumping stuff in the tank...they do it at the Schroeder valve....
chemicals like Gumout Fuel Injection cleaner work very well...they also eat the rubber piece in between the pump and line...this just makes the pump move fuel from the tank right back into itself....I have seen this hundreds of times...
chemicals like Gumout Fuel Injection cleaner work very well...they also eat the rubber piece in between the pump and line...this just makes the pump move fuel from the tank right back into itself....I have seen this hundreds of times...
Hi-Rev Motorsports
Joined: Aug 2009
Posts: 4,898
Likes: 65
From: Northern Indiana
some boosters will do it too...acetone makes a good octane booster in itself and that does weird things....
I use Lucas fuel additive...it will slightly boost the octane and will lube the system rather than kill it plus it cleans as well...I add a little every other tankfull and I do usually get better mileage off of it...
I use Lucas fuel additive...it will slightly boost the octane and will lube the system rather than kill it plus it cleans as well...I add a little every other tankfull and I do usually get better mileage off of it...
Thread Starter
Junior Member
Joined: Sep 2009
Posts: 15
Likes: 0
My father recently checked a relay by the pack of wires by the driver side fender pictured above and he picked up a reading with his meter, indicating that it's good. I told him about checking the fuel pressure and that's what he'll do next.
He has a gauge that he says he can check with, but what's the pressure reading you should get if there's no obstruction in the fuel lines? He discovered from Autozone that the truck's got two fuel pumps, one high and one low pressure. Would anyone happen to know where the fuel pump relay is located and where the inertia switch is on the 4.9L truck? Do both pumps run on one relay, or two relays?
Last edited by Plagueis; Oct 4, 2009 at 04:57 PM.
Grabber Green Consultant
Joined: Oct 2009
Posts: 85
Likes: 1
My father recently checked a relay by the pack of wires by the driver side fender pictured above and he picked up a reading with his meter, indicating that it's good. I told him about checking the fuel pressure and that's what he'll do next.
He has a gauge that he says he can check with, but what's the pressure reading you should get if there's no obstruction in the fuel lines? He discovered from Autozone that the truck's got two fuel pumps, one high and one low pressure. Would anyone happen to know where the fuel pump relay is located and where the inertia switch is on the 4.9L truck? Do both pumps run on one relay, or two relays?
and the fuel pressure you should get would be around 50 PSI Key On Engine Off...and about 45PSI Key On Engine Running
Thread Starter
Junior Member
Joined: Sep 2009
Posts: 15
Likes: 0
Travis, thank you very much for the clarification. I'll forward the information to him right away.
The relay he tested was what he thought was for the fuel pump, but now he's not sure. In any case, this relay did have a lot of corrosion on the inside, and he cleaned it and sprayed a lot of that electric cleaner stuff and put it back together. The next things on the list is checking the fuel pressure and fuel pump relay. Is the relay ever placed at different locations from truck to truck of the same model, or is it always located at a designated spot, like in the wire batch area pictured above?
Oh, to answer Farmer12, the mileage of this truck is unknown. The mileage gauge has only got 5 digits and it's currently at 20-something thousand. I would have to assume that it's got around 120k+ at the very least because the mileage reset to 0 after 99999 during his ownership.
The relay he tested was what he thought was for the fuel pump, but now he's not sure. In any case, this relay did have a lot of corrosion on the inside, and he cleaned it and sprayed a lot of that electric cleaner stuff and put it back together. The next things on the list is checking the fuel pressure and fuel pump relay. Is the relay ever placed at different locations from truck to truck of the same model, or is it always located at a designated spot, like in the wire batch area pictured above?
Oh, to answer Farmer12, the mileage of this truck is unknown. The mileage gauge has only got 5 digits and it's currently at 20-something thousand. I would have to assume that it's got around 120k+ at the very least because the mileage reset to 0 after 99999 during his ownership.
Last edited by Plagueis; Oct 4, 2009 at 05:48 PM.
Grabber Green Consultant
Joined: Oct 2009
Posts: 85
Likes: 1
Travis, thank you very much for the clarification. I'll forward the information to him right away.
The relay he tested was what he thought was for the fuel pump, but now he's not sure. In any case, this relay did have a lot of corrosion on the inside, and he cleaned it and sprayed a lot of that electric cleaner stuff and put it back together. The next things on the list is checking the fuel pressure and fuel pump relay. Is the relay ever placed at different locations from truck to truck of the same model, or is it always located at a designated spot, like in the wire batch area pictured above?
Oh, to answer Farmer12, the mileage of this truck is unknown. The mileage gauge has only got 5 digits and it's currently at 20-something thousand. I would have to assume that it's got around 120k+ at the very least because the mileage reset to 0 after 99999 during his ownership.
The relay he tested was what he thought was for the fuel pump, but now he's not sure. In any case, this relay did have a lot of corrosion on the inside, and he cleaned it and sprayed a lot of that electric cleaner stuff and put it back together. The next things on the list is checking the fuel pressure and fuel pump relay. Is the relay ever placed at different locations from truck to truck of the same model, or is it always located at a designated spot, like in the wire batch area pictured above?
Oh, to answer Farmer12, the mileage of this truck is unknown. The mileage gauge has only got 5 digits and it's currently at 20-something thousand. I would have to assume that it's got around 120k+ at the very least because the mileage reset to 0 after 99999 during his ownership.
Junior Member
Joined: Oct 2009
Posts: 1
Likes: 0
I don't know if you have ever replaced timing gear or not, but with distributor in and cap off crank engine to make sure distributor is turning. If not the timing gear has failed. The factory gear is made of a fiber material and deteriorates and breaks. The replacement is steel and will last a lifetime.