KCsTJ's 1997 Jeep Wrangler SE

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KCsTJ

KCsTJ

TJ student
Supporting Member
I impulse-bought the rivet style flares. I am rethinking that move and will sell them at some point. They will come off and the factory flares will go back on.

20180725_125502.jpg


The first thing I did was install new brakes and rotors.
The next thing I did was pull the cylinder head. The spark plugs were all white as could be indicating a lean and possible higher than normal temps.
So not knowing the history I pulled the head and had a complete valve job done for $200.
So at 152k miles it got basically a new cyl head, which did not correct the lean condition, btw.
The lean condition was corrected by the correct O2 sensor.
 
Last edited:
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KCsTJ

KCsTJ

TJ student
Supporting Member
Ugh, looks like I may have one of those 97 TJs with a bad batch of valve springs. Getting random misfires on cylinders 3 and occasionally on 3 & 4.
I think what I will do to troubleshoot this is switch the valve springs on cyls 3 and 2.
Then if I get a misfire on cylinder 2 I will know it's time to replace all valve springs.
168k on the clock.
 
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KCsTJ

KCsTJ

TJ student
Supporting Member
Thought I found the misfire problem...insulation stripped from both wires on inj#4. Repaired and ran great till today, another code 43 misfire. It has 2 stock injectors and 2 replacement injs
I think I may have to end up building a F.I.
wiring harness from scratch.
 
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Don Ashcraft

TJ Enthusiast
Nov 13, 2018
138
Kalamazoo, MI
I impulse-bought the rivet style flares. I am rethinking that move and will sell them at some point. They will come off and the factory flares will go back on.

View attachment 55535

The first thing I did was install new brakes and rotors.
The next thing I did was pull the cylinder head. The spark plugs were all white as could be indicating a lean and possible higher than normal temps.
So not knowing the history I pulled the head and had a complete valve job done for $200.
So at 152k miles it got basically a new cyl head, which did not correct the lean condition, btw.
The lean condition was corrected by the correct O2 sensor.
Mine was the same when I got it. 2.4l so I figured the sluggish performance was just a thing to get used too. On my third week of ownership I finally got the time to give her a tune up and found the plugs toasted and chalky white. Turned out that both my upstream and downstream O2 sensors were bad. after that and some other minor maintenance care, she runs like a beauty.
 
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KCsTJ

KCsTJ

TJ student
Supporting Member
Im still fighting random misfires after replacing the crankshaft position sensor.
Ordered a new set of valve springs and i should have them installed by next week.
Apparently i have one of the 97s with a bad valve spring batch. :/
$90 from wermopar
 
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KCsTJ

KCsTJ

TJ student
Supporting Member
Got a new set of valve springs from wermopar. Im having a local machine shop fabricate a simple valve spring compressor.
Got the new springs, just waiting on the valve spring compressor fab. from the machine shop.
20181205_142733.jpg

Hope to fire it up with no misfires in a couple days
 
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KCsTJ

KCsTJ

TJ student
Supporting Member
These are the valve springs im replacing.
Still waiting for a call from the machine shop re: my valve spring compressor.
So while I'm bored, here's what a 2.5L looks like with the valve cover removed..
20181205_142745.jpg

The metal pieces between the rocker arms are called rocker arm retainers. They are torqued to 19 ft lbs. Remove the retainers and the rocker arms can be pulled off.
Now you have access to the valve springs. The valve springs can now be removed 1 by 1, but only when the piston is at TDC or else the valve drops into the cylinder then we have loads of fun removing the cylinder head to retrieve the valve and i dont like thinking about that. :-/
Just can't be too careful that's the only risk, dropping a valve so i make sure i TDC the piston ! :)
 
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KCsTJ

KCsTJ

TJ student
Supporting Member
Just picked up my new modified valve spring compressor, made from a flat bar, I call it a cats paw.
I had a machine shop modify it slightly by cutting a u shape in the end and drillonf a hole for the rocker bolt...
20181208_162345.jpg

Here I have it in position to compress the valve spring.
20181208_162152.jpg
 
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KCsTJ

KCsTJ

TJ student
Supporting Member
This was causing the misfire...
See the missing insulation where the wires enter the fuel injector connector... under high load or highway driving it would arc between the bare wires causing a misfire.
20181222_080213.jpg

Zoom in and you can see the bare wires @ the connector.
Rough idle has smoothed out and my 2.5L runs smoother overall. The part number is STD S697, you can get a fuel injector connector for $7.50 at Oreillys.
Now I can turn my attention to my tranny temp gauge install project.