Hey guys!

I decided to go with the Howell EFI install on my 1988 YJ and WOWOWOWOWOW!!!!! What a difference!

I have to say that with my particular YJ, the Howell is like night and day. It starts right up, doesn't run rough, and there is a noticeable improvement in performance.

The install took about 8 hours and I confess, I had an expert mechanic do the install for me so it was installed correctly.

Post install I have an issue: high idle...mine likes to sit at 1500 - 2000 instead of 750 after it warms up...way too high!

I'm thinking it has something to do with the temp sensor (?). Anyone have this problem?

Thanks much!
Barb

The temp sensor for most if not all fuelies is simply a SWITCH that when reaching a certain temp tells the computer to go t the LEAN condition for normal running. Yes the switch can cause high idle.
Most likely there may be a vac leak and the computer is adjusting the fuel to make the engine run smooth and cover the lean condition.
Could also be the iac or the tps.. Not being familiar with the howell at all from here I would be simply guessing.
I would first look at a throttle stop to see if it could be advanced... if so I would atempt to retard the throttle if possible.
It could be that your pedal-cable assembly is holding the throttle open a small amount.
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />

Have you called Howell, and what did they have to say. I've been told that their tech support is pretty good.

I installed one about a year ago and must say it was the best thing I ever did. Although it took me about 16 hours, I did it myself. If anything, I learned a lot about the jeep while installing it.

Anyway, did you put a jumper across the A and B pin of the ALDL connector and check to see what code if any was blinking from the "check engine" light that was installed.
Normally, you will get a code "12" blinking three times and then if any errors, will follow after that.

Have you set the "minimum air rate" setting?
If not, the idle can hunt all over.

Also the more sensors you have, in respect to the same engine in an GM OEM application the better.

No Vehicle speed sensor (VSS), No Brake switch, No Park neutral switch, no air charge temp sensor? If not, get them. You may have to have the ecm prom reflashed.

Min air setting...air cleaner off, right above the IAC (Idle air control motor) on the side of the TB, is a vacuum passage, (snap on makes several special tools to do this) but a shop towel stuffed into that passage will effectivly block the air passing through. The idle should come way down, if not stall when you block that passage. While blocked, (unseal, if not already)the idle speed screw (torx) and adjust the idle to 400-500 rpm (trans in neutral).
Then pull the passage plug, shut off the engine, clear the memory (dissconect the battery for 30 minutes)restart and drive at least 2-3 drive cycles. A drive cycle is...start up drive for at least 5 minutes and during get to above 35 mph for 10-20 seconds then stop, shut off engine and repeat. If you have no VSS just drive for 20 minutes.

The IAC motor should relearn to set the idle speeds.

SD

Oh what fun! I gotta get me one of those! Sounds like somebody KNOWS what they are talking about...don't it?
Big Jim <img src="/forums/images/graemlins/pfft.gif" alt="" />

I don't know Big Jim, I didn't have to do all that when I installed it. I followed the directions and she started right up the first time.

If all the things Supe talked about are options in the setup...I'd be going for it. It may run Ok with minimum setup but if you can get more information into the computer...stands to reason better things would happen.
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />

You installed it, it ran and all is well? Or you wrote into a forum with a problem?

Of course they don't tell you to do all that tech stuff...
They would never sell any kits...

The tech stuff comes from 24 years of service on carbs and EFI systems.

If you get the basic kit you get basic run quality, with issues.

This in no way a knock on the tech that installed it, they may know all of what needs doing and may not want to do it under warranty. When I set one up I try and get those bugs worked out before delivery. But I charge 12-15 hours for the install, knowing I could see it back then fix it for free. Kits are not like OE systems. They omit key features to keep the price down, when I order a Howell kit, I spend 20-30 minutes on the phone making sure the kit fits the customers requests. If it needs to pass emissions tests, like 98% of the ones I do, the full emissions package nees to be installed. EGR with solenoids, EST with ecu controlled distributer, Knock sensors, VSS with calibrated speedo, park neutral and brake switches.

These kits cost close to twice what the basic kits costs.
Did you order a basic kit?

Did it come with a distributer? VSS? Single wire or 3 wire (heated) O2 sensor?

It all matters.

GM never intended for their TBI systems to be run without complete controls, allthough they did make them so they would run "ok" if a system or two failed...Rather than shutting down. You are not the first one to complain about an idle issue with a Howell system. As simple as changing the PCV valve (to one with a smaller or larger orifice)can have huge results in correcting several types of idle prolems.

So...don't feel bad or ripped off or that I'm picking on you, I'm here to help. If you need to spend more money to get it right, so be it. Kits...don't you love them.
Also I've installed several brands of aftermarket TBI and EFI systems...Howell is far and away the best, and if you know what to ask them, their tech department is excellent.

SD



SD

I realize you weren't picking on anyone and the wealth of information is always welcome.

Although, I have not gone through inspection since putting on the TBI are you indicating that it may not pass?