Fuse for Howell Fuel Injection

edgregorio

New Member
Joined
Dec 15, 2021
Messages
9
Location
Magalia
Hello,

I have a 1990 Jeep Wrangler 4.2 with a Howell fuel injection system. The fuel injection system suddenly stopped working, which makes me think that it might possibly be a fuse issue. (A couple of weeks ago, I was checking the fuses to deal with a horn issue and am wondering if I pulled out the fuse for the fuel injection system and did not reinsert it correctly.) Is there a fuse with the Howell EFI? If so, where would I locate it? Any other causes for the sudden loss of FI?

Thank you,

Ed
 
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edgregorio

edgregorio

New Member
Joined
Dec 15, 2021
Messages
9
Location
Magalia
Doing some online research. The check engine light is not coming on and I am not hearing the fuel pump when I turn the key. Is there a fuse for the fuel pump for a 1990 Wrangler 4.2. Where would I locate the grounding wire for the fuel pump?
 

machoheadgames

Certified YJ Researcher
Supporting Member
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May 19, 2020
Messages
1,290
Location
Dallas, TX
Howell PCM might be bad. Factory 1990 4.2 won’t have an electric fuel pump, it has a mechanical pump. I believe the Howell adds an electric pump inline and you’re supposed to mount it to the fuel rail. So maybe find that and follow the wiring for it.

In a typical YJ with fuel injection, no check engine light or fuel pump means the pcm capacitors are bad. Not sure how that GM computer in the Howell kit works but I imagine it’s similar. Never seen anyone post this problem with the Howell tbi before.
 

Gilaguy23

YJ Enthusiast
Joined
Apr 12, 2021
Messages
572
Location
Q town New Mexico
My 86 CJ7 had the Howell FI installed on it. First off IIRC you can visit Howells website and download a install guide which may help you in the future. Yes,on mine it used a frame mounted generic electric fuel pump. I cant recall specifically where it got its power from but Id guess the ECM so id have to say it has fused power off the key or other keyed source. Its basically a Chevy 4.3 V6 TB and associated parts to make it work. Howell gives the GM part numbers for pretty much every part last I looked. The only real one off part is their adapter to go between the TB and intake.