I'm having a similar problem on my 88 Renix 4.0 XJ, except mine stalls out more times than not, then runs rough IF I can get it started back.
I'll be monitoring this post for you progress and and let you know mine as well (for what it's worth - I know there's a bit of difference in those 11 years and Renix v. OBD, but you never know what might help.)
So far I changed the fuel pump ballast resistor, but still stalls out at operating temperature ($6 part, at least 20 years old so no biggy). I'm about to replace my IAC as well - same logic, it's due a swap either way.
When I reviewed a Jeep training doc for 87-90 Renix system, I found under "Modes of Operation" section that in "Warm-up Mode, Open Loop" the idle is set by the ECU based on coolant temp sensor input by sending a control signal to IAC. Gonna have a look at that next if the new IAC doesnt fix it. Not trying to hi-jack your thread, just passing it on in case the info can be of any use to you. Hope it helps.
I'll be monitoring this post for you progress and and let you know mine as well (for what it's worth - I know there's a bit of difference in those 11 years and Renix v. OBD, but you never know what might help.)
So far I changed the fuel pump ballast resistor, but still stalls out at operating temperature ($6 part, at least 20 years old so no biggy). I'm about to replace my IAC as well - same logic, it's due a swap either way.
When I reviewed a Jeep training doc for 87-90 Renix system, I found under "Modes of Operation" section that in "Warm-up Mode, Open Loop" the idle is set by the ECU based on coolant temp sensor input by sending a control signal to IAC. Gonna have a look at that next if the new IAC doesnt fix it. Not trying to hi-jack your thread, just passing it on in case the info can be of any use to you. Hope it helps.
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cruiser54
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May 16, 2024
- Join DateAug 2011
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- Year1990
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Quote:
I'll be monitoring this post for you progress and and let you know mine as well (for what it's worth - I know there's a bit of difference in those 11 years and Renix v. OBD, but you never know what might help.)
So far I changed the fuel pump ballast resistor, but still stalls out at operating temperature ($6 part, at least 20 years old so no biggy). I'm about to replace my IAC as well - same logic, it's due a swap either way.
When I reviewed a Jeep training doc for 87-90 Renix system, I found under "Modes of Operation" section that in "Warm-up Mode, Open Loop" the idle is set by the ECU based on coolant temp sensor input by sending a control signal to IAC. Gonna have a look at that next if the new IAC doesnt fix it. Not trying to hi-jack your thread, just passing it on in case the info can be of any use to you. Hope it helps.
Originally Posted by PapaBearXJ88
I'm having a similar problem on my 88 Renix 4.0 XJ, except mine stalls out more times than not, then runs rough IF I can get it started back.I'll be monitoring this post for you progress and and let you know mine as well (for what it's worth - I know there's a bit of difference in those 11 years and Renix v. OBD, but you never know what might help.)
So far I changed the fuel pump ballast resistor, but still stalls out at operating temperature ($6 part, at least 20 years old so no biggy). I'm about to replace my IAC as well - same logic, it's due a swap either way.
When I reviewed a Jeep training doc for 87-90 Renix system, I found under "Modes of Operation" section that in "Warm-up Mode, Open Loop" the idle is set by the ECU based on coolant temp sensor input by sending a control signal to IAC. Gonna have a look at that next if the new IAC doesnt fix it. Not trying to hi-jack your thread, just passing it on in case the info can be of any use to you. Hope it helps.
Best thing you could do is go to www.cruiser54.com and complete Tips 1 through 5 first.
Clean your throttle body. There's a Tip for that also.
Make sure your intake manifold nuts are snug.