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JHo303 07-13-2013 06:51 AM

Well, failed the first try...didnt have alot of hope. After fixing idle problems by cleaning out the venturi tubes (thnx Forum), Jeep runs great until you stick your foot in it too far. Then it bogs down really bad. Failed on "High HC" (unburned fuel) and "High CO" (air/fuel mix too rich). Stock Carter BBD and air cleaner. It does have a whistle that is consistent with engine RPM, which I assume is a vacuum leak. Is that where I start to just get it through emissions?
Thanks, Jim

jokerchief462 07-13-2013 02:16 PM

Yes that would be a good place to start. Also check this site for some good info.

Old4X 07-13-2013 03:18 PM

What is the altitude at your test site? There is a high altitude jumper for YJs based above 4,000 ft msl (or close, cna't remember the exact figure). You will be out os spec on the rich side if you do not use the jumper.

It is mentioned in the factory maint manual, and has been written up here several times.

jay-h 07-14-2013 06:03 AM

I've got some stock carb & hookup parts if you need them.

JHo303 07-14-2013 07:37 AM

Thanks for the replies...think I'll just sell out and get the Howell TBI

laybackman 07-14-2013 08:07 AM


Originally Posted by JHo303 (Post 15674715)
Thanks for the replies...think I'll just sell out and get the Howell TBI

Not to pee in your pool but that may only lighten your wallet but not fix your problem. You don't just slap on the TB set up and drive off into the sunset.

If you have a vacuum leak, find it! Stick your head under the hood while it is running and find the leak first. You may only need to tighten the bolts that hold the carb on the intake.

Spend you $$$ on something else!

Keep this in mind....that YJ of yours ran perfect at one time. Find out what changed and fix it!

SLCSmoker 07-14-2013 08:49 AM

I disagree completely with the above post. I went through all this about 8 months ago. Ripped off the carb and put howell FI on. Best $ I've spent on the Heep. The vacuum system is 100x simpler with the howell and it passed emissions cleaner than the stock vehicle brand new. Its not a waste of $$. I say do it and save yourself a ton of headaches with the POS stock carb. It also allows you to tear out about 60 feet of redundant wiring and really clean everything up.

NonRubicon 07-14-2013 10:19 AM

If you want the upgrade to simplify the setup and get better performance, then do the Howell. But be careful thinking that the Howell will solve all problems. Double check your intake manifold - retorque all the bolts to spec and do the carb spray trick to check for vacuum leaks. The Howell will not fix a bad intake/exhaust manifold gasket, nor will it fix a crack in the exhaust manifold and both can cause a fail. So, if you are set on doing the Howell, I highly recommend you track down that vacuum leak whistle, before doing the kit. And for good measure make sure the exhaust manifold doesn't have any cracks. That'll cause a rich condition too by messing with the O2 sensor.

With that said, I found the Howell to be a vast improvement in simplicity and increased performance over the OEM setup. I used to spend entire weekends under the hood f-ing with the OEM setup trying to diagnose and track down a simple problem. A TBI setup like the Howell is what Jeep should have put on the 4.2L YJ in the first place, but I suppose it was easier and cheaper to just keep using the CJ components.

The_Goob 07-14-2013 11:47 AM

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Sometimes Im glad I live in Iowa and dont have to do emissions :P

jay-h 07-14-2013 07:21 PM

While it's true the Howell can't solve all the problems, it gets rid of a lot of the vacuum lines and controls and meters the fuel more accurately. Assuming your engine is decent it should work. I'm quite pleased with mine

Keep in mind that there are two Howell versions, only one is actually EPA approved. Both may well pass the sniffer test but in a lot of places you need the approved one.

JHo303 07-16-2013 08:44 PM

$1375.00 including shipping and a new Prom that lets us wheel at higher elevation. Going to replace the intake gasket while I wait for the Howell to get here. Should be a hoot!

The time now is 12:50 AM.

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