I have a 1988 22RE pickup. My problem is that the hot wire that is coming into the fuse box for the EFI relay is getting hot and melting the fuse. I have run a direct wire from the battery into the fuse box but it still heats the fuse and the relay up. So I think it might be the mass air flow sensor, but I'm not sure. Anybody got any ideas?

 

Check Main Relay And Connecting Relay.......could Be Bad

 

Find out what is pulling too much current on that circuit. Common cause is an O2 sensor wire that has fallen against the hot exhaust, melting the insulation and causing a short.

 

Take the black top off the AFM and make sure all the little metal contacts are facing up and not touching any other of the contacts...thats what happened to me...

 

Hi all,
I went to wash my truck yesterday and rinsed the underbody near the motor and the check engine light began flashing. Drove for 7 miles, gassed up and proceeded, when the truck died. Its turning over but no fuel from fuel pump to filter. Replaced the fuel pump, but still no start. Found a bad EFI fuse (located on right in underhood fuse box) to replaced, tried again, but fuse blew again. Any advice would help. Thanks. DJ

 

Likely a wire to the O2 sensor has shorted out either with the water or by touching the hot exhaust and melting the insulation. Check the stored code:
- http://www.4crawler.com/4x4/CheapTri...CheckConnector

 

Thanks for reply 4Crawler,
Slight progress. The vehicle started, drove it for a couple miles but the fuse burnt out again.

 

Hi all,
With the help here, I discovered small cracks near the base of the O2 sensor plug wires at the exhaust manifold. Elec taped them and no more blown fuse, however, the CEL flashes every now and then. Wondering if I gotta get a new O2 sensor now. The DD truck runs though and thanks, esp to 4Crawler. DJ

 

Hello again,
I was ok there for a few weeks, until this morning after 30 miles of travel on melted snow slush puddles (wet). I pulled over on the side of the road to let my dogg off. I went to start the truck, nothing...took out 3 fuses instantly. Girlfriend came in the 4Runner, towed truck for 10 miles and let it sit at a store for about 3 hours. Came back to the truck to tow it again but she said maybe it dried by now. I throw a new fuse in there and fires up andI returned. Lost confidence now that the girlfriend knows wuts up with the truck. Any suggestions would help. Thanks again. DJ

 

Would help to tell us what fuses are blowing out, or is it one fuse blowing out 3 times in a row? Find out what items are on the circuit of the fuse(s) that are going out and try systematically eliminate things on that circuit until the fuse no longer blows out.

 

That would help, sorry.
It is the EFI fuse (15) that blows out and did blow out after 3 replacements in a row this morning. Thanks. DJ

 

i'd check your pervious fix on the 02 sensoe wire.. really clean it up and seal it nicely.