Who wants more power out of their 87 or 88?
#76
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#77
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
#78
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Here's some comparison photos between the stock Renix 52mm throttle body, a 60mm Renix throttle body, and an HO throttle body:
#79
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Year: 1986
Model: Cherokee
Engine: 2.5l I4 TBI
Mine has weird idle issues, so due to that and the reported HP increases, I plan on snagging a new one from the local pick 'n pull ASAP. Local yard actually has a few 2.5l XJs in the 89-90 year range, so I'll report back once I get the swap made.
#80
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
My '86 TBI 4 banger's factory ECU is pn S100801103A. It's missing the label that would have the year week on it like I've seen in other pictures, but the small label that has the pn on it also has the 4 digit as well, and mine is 8543 I think - so again making sense that it's a late '85 date on it.
Mine has weird idle issues, so due to that and the reported HP increases, I plan on snagging a new one from the local pick 'n pull ASAP. Local yard actually has a few 2.5l XJs in the 89-90 year range, so I'll report back once I get the swap made.
Mine has weird idle issues, so due to that and the reported HP increases, I plan on snagging a new one from the local pick 'n pull ASAP. Local yard actually has a few 2.5l XJs in the 89-90 year range, so I'll report back once I get the swap made.
#81
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Year: 1987
Model: Cherokee
Engine: Renix 4.0
Just reading through this and would like to thank everyone for sharing so far.
For those of you who have upgraded their ECU to 89/90, what was your MPG gain?
I'm pretty happy with my 19ish MPG with stock lift, 30" tires, and 746 injectors. Would love to have more power and smoother idle from a ECU upgrade, but don't want that at the loss of fuel mileage. Thanks in advance for any info!
For those of you who have upgraded their ECU to 89/90, what was your MPG gain?
I'm pretty happy with my 19ish MPG with stock lift, 30" tires, and 746 injectors. Would love to have more power and smoother idle from a ECU upgrade, but don't want that at the loss of fuel mileage. Thanks in advance for any info!
#82
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Year: 1987
Model: Cherokee
Engine: Renix 4.0
#84
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Just reading through this and would like to thank everyone for sharing so far.
For those of you who have upgraded their ECU to 89/90, what was your MPG gain?
I'm pretty happy with my 19ish MPG with stock lift, 30" tires, and 746 injectors. Would love to have more power and smoother idle from a ECU upgrade, but don't want that at the loss of fuel mileage. Thanks in advance for any info!
For those of you who have upgraded their ECU to 89/90, what was your MPG gain?
I'm pretty happy with my 19ish MPG with stock lift, 30" tires, and 746 injectors. Would love to have more power and smoother idle from a ECU upgrade, but don't want that at the loss of fuel mileage. Thanks in advance for any info!
#85
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
#87
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Year: 1990
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#88
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Year: 1990
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Alright, any progress reports?
#89
Seasoned Member
So this is the sticker on my ecu in my 90. I had to replace the ecu a few years ago and was told this is for a a/t 4.0. Is it the right one?
#90
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0