Howell EFI install problems - JeepForum.com
 
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post #1 of 8 Old 09-25-2020, 07:22 PM Thread Starter
MuloChico
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Howell EFI install problems

Well, I finally got the kit installed. Problem is that I am getting a flashing CEL. I am in the process of going thru their procedures to diagnose, but it isn't really covering much with the flashing light. Of course it is Friday evening so I won't be able to contact Howell until Monday.

Everything is hooked up. As I said, CEL is flashing. If I short the diagnostic ports it only gives a code 12 which is the standard to let you know the diagnostics are working. It's getting fuel, no spark. I haven't dove into it very far, that will be on Sat. Just looking for ideas to cut the diagnostic process as short as possible.

Any direction as to where is the most likely place? Thanks in advance.

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post #2 of 8 Old 09-27-2020, 01:04 PM Thread Starter
MuloChico
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Well, I always knew I was oddball . I'm going to start today with double checking all the wires (not only connections but that they go to where they are supposed to). Since no spark I will start there. I will update as I find issues. If I don't find anything then it is a call to Howell tomorrow.
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post #3 of 8 Old 09-27-2020, 07:39 PM
HuckUSN
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Any update?

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post #4 of 8 Old 09-27-2020, 11:52 PM Thread Starter
MuloChico
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Ended up not looking at it until Sunday. All the wires are connected as per the instructions. The CEL still flashes when the key is on. I got it to start twice. It has a miss and it seems to be over fueling. On Monday I am going to try to test to see it the return line is clogged (to much pressure in the fuel lines as per the Howell troubleshooting instructions). A bit of progress, but it is going to take a bit of time. It has an alarm from the previous owner that might be wired weird judging buy what we have found in the past. I don't think it is the Howell system, just old mods/repairs that need to be worked thru for this to work. I will keep this updated as I find out more.
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post #5 of 8 Old 09-28-2020, 07:14 PM
1project2many
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Flashing CEL does not usually indicate mechanical issues such as a plugged fuel line. There are different conditions that can cause the light to flash, and how it flashes has different meanings.

Key initially turned on, engine not running. CEL lights for approximately 5 seconds, then turns off for 3-5 seconds, then turns on and stays on: ECM has just checked to see if the chip is corrupt and has detected no problems.

Key initially turned on and engine not running. CEL lights and stays on, or CEL flashes rapidly, or CEL flashes slowly: Problem with chip, or data in chip, or connection between chip and board. Try to wiggle chip. Check for bent pins in adapter. Chack for bad connection. Wiggle chip. If nothing works get a known good chip.or ecm.

Key on, engine running: Rapid flashes equally timed = open loop

Key on, engine running: Slower flashes, more time on than off = closed loop, rich operation
Slower flashes, more time off than on = closed loop, lean operation
Note: This should only occur if pins A and B of the ALDL are shorted.

The distributor can create spark when the ecm is dsconnected. You should be able to disconnect the four wire connector at the distributor then crank the engine to confirm spark is present. If you do not get spark while cranking you should start by diagnosing a basic no-spark issue before moving on to diagnosing a potential ecm problem. If you can find it, the "Cranks but won't start" diagnostic chart from section 6E-3A of a 1989 or 1990 C/K 1500 FSM should walk you through enough tests to figure out what's going on. If you're handy you might be able to use a DVOM and old spark plug to DIY the tests.
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post #6 of 8 Old 09-29-2020, 11:18 AM Thread Starter
MuloChico
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Quote:
Originally Posted by 1project2many View Post
Flashing CEL does not usually indicate mechanical issues such as a plugged fuel line. There are different conditions that can cause the light to flash, and how it flashes has different meanings.

Key initially turned on, engine not running. CEL lights for approximately 5 seconds, then turns off for 3-5 seconds, then turns on and stays on: ECM has just checked to see if the chip is corrupt and has detected no problems.

Key initially turned on and engine not running. CEL lights and stays on, or CEL flashes rapidly, or CEL flashes slowly: Problem with chip, or data in chip, or connection between chip and board. Try to wiggle chip. Check for bent pins in adapter. Chack for bad connection. Wiggle chip. If nothing works get a known good chip.or ecm.

Key on, engine running: Rapid flashes equally timed = open loop

Key on, engine running: Slower flashes, more time on than off = closed loop, rich operation
Slower flashes, more time off than on = closed loop, lean operation
Note: This should only occur if pins A and B of the ALDL are shorted.

The distributor can create spark when the ecm is dsconnected. You should be able to disconnect the four wire connector at the distributor then crank the engine to confirm spark is present. If you do not get spark while cranking you should start by diagnosing a basic no-spark issue before moving on to diagnosing a potential ecm problem. If you can find it, the "Cranks but won't start" diagnostic chart from section 6E-3A of a 1989 or 1990 C/K 1500 FSM should walk you through enough tests to figure out what's going on. If you're handy you might be able to use a DVOM and old spark plug to DIY the tests.
Thanks for confirming my suspicions on the cel, I had planned to check the ECM chips and that just confirms it for me. I didn't think the flashing cel was from the clogged fuel line, that was a separate thing from the over fueling that I noticed when it did run.

Also, thanks for the reference to a service manual, Howell gives a pretty good problem solving supplement, but the manual would more than likely be more in depth. Your input has given me more direction on the diagnostic. It might be a week or 2 before I get to involved because of work, etc. I will update as info comes in.
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post #7 of 8 Old 10-13-2020, 12:45 PM Thread Starter
MuloChico
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Well, found out a few things and made a lot of progress.

As far as thee CEL: I ended up calling Howell. They were very informative. It ends up because the EFI is based on a late 1980's computer it doesn't work with LED lights very well. Switched to a standard bulb and the CEL works as it is supposed to.

The "over fueling" issue ended up being the #4 and #6 plug wires got switched. I don't know how, but a friend was over and he caught it. I had not messed with the plug wires so who knows what happened, but it runs great now. Fires up every time.

Time to start packaging the old wiring up as I delete all the unused connections. Hopefully should get done with that by this weekend. I still have to make the speed sensor for the system look good to be Ca legal. Howell said it doesn't really do anything but make CARB (Ca Air Resources Board) happy so if I can make it look good it should not have any problems.

I also have to track down a leak in the Evap system. Probably the roll over valve. We will see. Then it is off to get it smogged, then registered and my son will finally have his Wrangler back (and I get my f250 back)
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post #8 of 8 Old 10-13-2020, 03:02 PM
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Quote:
Originally Posted by MuloChico View Post
Well, found out a few things and made a lot of progress.

As far as thee CEL: I ended up calling Howell. They were very informative. It ends up because the EFI is based on a late 1980's computer it doesn't work with LED lights very well. Switched to a standard bulb and the CEL works as it is supposed to.

This is good to know.

Whats over that next ridge?
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