Yes Another renix low idle problem
Thread Starter
Member
Joined: Jun 2017
Posts: 159
Likes: 0
From: Yakima, WA Pacific Northwest
Year: 1990
Engine: 4.0 renix
Thread Starter
Member
Joined: Jun 2017
Posts: 159
Likes: 0
From: Yakima, WA Pacific Northwest
Year: 1990
Engine: 4.0 renix
Got the dipstick ground taken care of. Now I'm getting 1.5 ohms instead of 4 so I'm making progress lol. I'm going to some more wire jiggling with the volt meter in there but I'm thinking a #6 is in order. Seems like when I take care of one problem another pops it's ugly head up. But I know all this stuff I'm learning will help me when I FINALLY get on the road/trail
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,578
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Got the dipstick ground taken care of. Now I'm getting 1.5 ohms instead of 4 so I'm making progress lol. I'm going to some more wire jiggling with the volt meter in there but I'm thinking a #6 is in order. Seems like when I take care of one problem another pops it's ugly head up. But I know all this stuff I'm learning will help me when I FINALLY get on the road/trail
Thread Starter
Member
Joined: Jun 2017
Posts: 159
Likes: 0
From: Yakima, WA Pacific Northwest
Year: 1990
Engine: 4.0 renix
Hit a road block (puns are fun). Got everything opened up and started tracing wires for procedure #6 and realized that the iat and map sensor wires both meet at the same splice. There are 5 wires going into one right by the map sensor and the single wire is headed toward the passenger fender. Should I trace back from the tps or cts to find the other splice??
Thread Starter
Member
Joined: Jun 2017
Posts: 159
Likes: 0
From: Yakima, WA Pacific Northwest
Year: 1990
Engine: 4.0 renix
Hit a road block (puns are fun). Got everything opened up and started tracing wires for procedure #6 and realized that the iat and map sensor wires both meet at the same splice. There are 5 wires going into one right by the map sensor and the single wire is headed toward the passenger fender. Should I trace back from the tps or cts to find the other splice??
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,578
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Thread Starter
Member
Joined: Jun 2017
Posts: 159
Likes: 0
From: Yakima, WA Pacific Northwest
Year: 1990
Engine: 4.0 renix
Will do..there is another right by it that goes to the dipstick ground too. Looks like the grounds for the injectors (6 wires, one coming from each injector and 2 more from who knows where) going to perform the same procedure but I think I'm going to us a 10g wire. and again, I really appreciate u holding my hand thru this cruiser. Awesome to know there are people out there willing to share their knowledge and experience just to help one another!! If u ever have any questions on flooring haller at me!! I've installed for 14 yrs. I wanna return the favor if I can lol
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,578
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Will do..there is another right by it that goes to the dipstick ground too. Looks like the grounds for the injectors (6 wires, one coming from each injector and 2 more from who knows where) going to perform the same procedure but I think I'm going to us a 10g wire. and again, I really appreciate u holding my hand thru this cruiser. Awesome to know there are people out there willing to share their knowledge and experience just to help one another!! If u ever have any questions on flooring haller at me!! I've installed for 14 yrs. I wanna return the favor if I can lol
Thread Starter
Member
Joined: Jun 2017
Posts: 159
Likes: 0
From: Yakima, WA Pacific Northwest
Year: 1990
Engine: 4.0 renix
Got those splices soldered together and it definitely helped but hasn't fully solved my problem. The throttle response seems a lot better and the idle doesn't drop as low and isn't as erratic after it drops. I'm getting between 1 and 1.2 ohms at the tps. What now? I poked around with the volt meter trying to find something with high resistance but no luck.
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,578
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Have you adjusted your TPS since fixing the grounds?
How's the tube from your throttle body to MAP sensor?
O2 sensor could cause those symptoms.
How's the tube from your throttle body to MAP sensor?
O2 sensor could cause those symptoms.
Thread Starter
Member
Joined: Jun 2017
Posts: 159
Likes: 0
From: Yakima, WA Pacific Northwest
Year: 1990
Engine: 4.0 renix
tps was reset and I replaced that vac line fairly recently (double ended barb in the t-body) but the idle has evolved into progressively getting lower as the vehicle warms up temp goes up=idle goes down. If I have a crack in the header could that be throwing off the O2? I know they can come faulty out the box but it also was recently replaced.
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,578
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
tps was reset and I replaced that vac line fairly recently (double ended barb in the t-body) but the idle has evolved into progressively getting lower as the vehicle warms up temp goes up=idle goes down. If I have a crack in the header could that be throwing off the O2? I know they can come faulty out the box but it also was recently replaced.
I can't imagine a crack in a header, a pressurized system, letting air IN.


