Howell Fuel Injection -
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Unread 05-06-2013, 08:44 PM   #1
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1980 CJ7 
Join Date: Sep 2010
Location: Park City, Utah
Posts: 50
Howell Fuel Injection

Hey Folks, i have a 1980 CJ7 with a 304. The 304 has about 6000 miles on a rebuild. It runs strong, idled well with a carb, no issues prior to installing a Howell TBI conversion. I now have a rough idle with a rolling idle. I hooked up a code reader and it states codes 33 and 34. It swaps back and forth and sometimes states both at the same time. Both codes at the same time doesn't make sense as they contradict each other. One means high MAP, the other reads Low MAP. Codes 33 and 34. I have good voltage, steady vacuum, good fuel pressure. I replaced the MAP sensor. Howell thinks it might be a bad ECM. Any ideas. The unit is way out of warranty as it sat in storage for a couple of years or I would send it back. It was stored in the box it came in. Any help would be greatly appreciated. Cheers, Jack

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