C223 Low MPGs question

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robgt22
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Posts: 372
Joined: Sat May 30, 2015 2:30 pm
Location: Guatemala
Isuzu vehicle(s): 95 honda passport, c223 swap. 01 trooper, 4jg2 swap

C223 Low MPGs question

Postby robgt22 » Wed Nov 08, 2017 2:49 pm

I've felt a massive drop in my mpgs these days, I would say I'm getting around 15-20mpgs, I know I'm running on 31x10.50's mt and that I'm on a heavy truck, but I don't think it should be that bad. I'm getting little to no black smoke, another thing to mention is I also feel I have very little low end torque, when launching on a small hill I have to really ride on my clutch to get out of it, every suggestion is very appreciated. Thanks everyone
95 Honda passport with a c223 swap. Garrett gt1749, 15 psi of boost. Straighpiped and intercooled. 2” lift, ball joint flip, 1 1/2” diff drop. 33x12.5 R15 tires, 12000 pound winch.

01 Trooper with a 4jg2 swap

dorf
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Re: C223 Low MPGs question

Postby dorf » Wed Nov 08, 2017 6:36 pm


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puttputtinpup
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Location: Winston Salem, NC

Re: C223 Low MPGs question

Postby puttputtinpup » Thu Nov 09, 2017 3:18 am

Just in case you haven't done this yet, look through this post of technical bulletin scans. The screen and pinholes in the banjo bolts in particular. Click on the link in my signature, or here viewtopic.php?f=1&t=4809&p=28779&hilit=technical+bulletins+timing#p28779

But to begin with, I'd do what Dorf said...Change the fuel filter. When I didy filter change, I used the advice of a once active member to warm up the engine good. Remove the old filter, swap the sensor being careful not to break the brittle sensor. Prefill the new filter with ATF , reinstall, and fire it up. May stumble a bit at first, but keep it running.

Also, be sure you fuel cap is venting properly

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puttputtinpup
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Posts: 10285
Joined: Sat Oct 08, 2005 5:18 am
Location: Winston Salem, NC

Re: C223 Low MPGs question

Postby puttputtinpup » Thu Nov 09, 2017 3:29 am

But...Before doing any work to the fuel system, the glow plug issue (in your other thread) has to be fixed.

robgt22
Regular Member
Posts: 372
Joined: Sat May 30, 2015 2:30 pm
Location: Guatemala
Isuzu vehicle(s): 95 honda passport, c223 swap. 01 trooper, 4jg2 swap

Re: C223 Low MPGs question

Postby robgt22 » Tue Nov 14, 2017 9:10 am

My fuel filter is less than 3 months and around 1500 miles. Might it still be clogged? I already cleaned the screen filters inside the bolts. The inlet one didn't look too bad but sure the return one was clogged. I was thinking about timing? I did mess with it when I installed the turbo so might it be too advanced? I've read that advancing timing too much will kill low end torque?
95 Honda passport with a c223 swap. Garrett gt1749, 15 psi of boost. Straighpiped and intercooled. 2” lift, ball joint flip, 1 1/2” diff drop. 33x12.5 R15 tires, 12000 pound winch.

01 Trooper with a 4jg2 swap