Calgary Jeep Association

4x4 Related Groups => Tech Talk => Topic started by: blackcherekee on August 08, 2014, 11:49:30 PM

Title: 90 cherokee fuel ballast resistor problem ?
Post by: blackcherekee on August 08, 2014, 11:49:30 PM
I think I may have a problem with my fuel ballast resistor my jeep starts and idles fine and drives fine until it gets hot then it loses all power. Any body else have/or had the same issue?
Title: Re: 90 cherokee fuel ballast resistor problem ?
Post by: Sean778 on August 09, 2014, 09:01:02 AM
Have you tried bypassing the resistor when it's hot to see if it makes a difference?
Title: Re: 90 cherokee fuel ballast resistor problem ?
Post by: ARBXJ on August 09, 2014, 08:19:43 PM
http://www.pirate4x4.com/tech/billavista/PDFs/Jeep_Renix_Fuel_Injection_manual.pdf

I an no mechanic but somewhere in this reference manual lies your answer. I have a 1990 but haven't run across this problem. Given it runs and then shuts down when hot, it is probably some kind of resistor related issue. Check the primary and secondary resistance across the coil? Are all the electrical contacts clean and soldered? This was a problem with the Renix system-contacts gunked up? Let me know if this doesn't download and hope the manual helps more than my comments, regards ARBXJ
Title: Re: 90 cherokee fuel ballast resistor problem ?
Post by: cLAY on August 10, 2014, 06:49:47 PM
Remove the wires from the resistor and splice them directly together. The resistor was added to cut down the noise the fuel pump makes. It wasn't even used on earlier models but was added in later as customers complained about noisy pumps.
Title: Re: 90 cherokee fuel ballast resistor problem ?
Post by: blackcherekee on August 11, 2014, 01:06:20 PM
So I have spliced the wires and still no luck I'm thinking maybe it's the thermostat
Title: Re: 90 cherokee fuel ballast resistor problem ?
Post by: dubbleJs on August 11, 2014, 02:22:34 PM
I think I may have a problem with my fuel ballast resistor my jeep starts and idles fine and drives fine until it gets hot then it loses all power. Any body else have/or had the same issue?

Does it overheat? Or by 'hot' do you mean running temperature?
Title: Re: 90 cherokee fuel ballast resistor problem ?
Post by: blackcherekee on August 11, 2014, 02:45:23 PM
When it hits running temperature
Title: Re: 90 cherokee fuel ballast resistor problem ?
Post by: cLAY on August 11, 2014, 03:31:27 PM
Why do you suspect the ballast resistor? Or do you have low fuel pressure?
Title: Re: 90 cherokee fuel ballast resistor problem ?
Post by: smacd11 on September 02, 2014, 11:19:26 AM
Did you get this solved?  My '89 was acting like that last year.  I too suspected fuel pressure problems, tested it - ok.  Replaced crankshaft position sensor - fixed.