My Jeep Wrangler Bogging, sputtering and losing acceleration

4th owner to wrangler 97. Had problems with backfiring/sputtering/loss acceleration. went to every site tracking down this problem. Finally followed steps to clean PCM (powertrain control module located above battery on passenger side) connectors, and secured them with wireties. Also secured two connectors to the right with wireties and padded to firewall. Also noticed problem existed as with others when turning, so I repositioned the battery with it's own clamps to keep it from shifting/rubbing against wire harness to pcm. so far this appears to have helped!!

Now have a muffled backfiring/stalling after a 25min cool down. Noticed my evaporator surge valve/solenoid was not working, also lines contained deposits, and main line to intake manifold contained large carbon deposits. Replacing valve and canister, could be having a problem with vapors not reaching manifold and adding to lean mixture that appears to result in backfiring (as I've been told). Also going to try alittle jet/carb cleaner into manifold to see if this helps clean carbon.
 
Now have a muffled backfiring/stalling after a 25min cool down. Noticed my evaporator surge valve/solenoid was not working, also lines contained deposits, and main line to intake manifold contained large carbon deposits. Replacing valve and canister, could be having a problem with vapors not reaching manifold and adding to lean mixture that appears to result in backfiring (as I've been told). Also going to try alittle jet/carb cleaner into manifold to see if this helps clean carbon.

also noted that battery was sliding into PCM connectors, placed rubberized mat under battery and added 1" spacer to rear battery clamp to help push battery forward to help stop irratic firing. Finally after researching 20 cool down backfiring/stalling and talking with auto tech, suggested 02 sensor may be problem, replace in and it did the thrick. What I've learned is that sensors appear to control everything through the PCM which just tries to react to what it's reading. And thanks for all the pervious posts to help me troubleshoot these problems.
 

Need help asap!! I have a 97 wrangler and the cel came on a week or 2 later my jeep cut off on thehighway all the sudden bog down... then i tried to start it ran a few seconds rpms jumping around 300rpms . Towed it home let it sit a while and it cranked up ran fine and the same thing has happened twice ill let it sit and it wil run fine and cut off after a little while of driving say 10-20 miles
 
Need help asap!! I have a 97 wrangler and the cel came on a week or 2 later my jeep cut off on thehighway all the sudden bog down... then i tried to start it ran a few seconds rpms jumping around 300rpms . Towed it home let it sit a while and it cranked up ran fine and the same thing has happened twice ill let it sit and it wil run fine and cut off after a little while of driving say 10-20 miles

What's the code?

Sent from my Samsung Galaxy S3 using Jeepz
 
Need help asap!! I have a 97 wrangler and the cel came on a week or 2 later my jeep cut off on thehighway all the sudden bog down... then i tried to start it ran a few seconds rpms jumping around 300rpms . Towed it home let it sit a while and it cranked up ran fine and the same thing has happened twice ill let it sit and it wil run fine and cut off after a little while of driving say 10-20 miles

Welcome to the Z.

With the key off, push and hold the odometer reset button.
Turn key to run (not start).
Turn key off.
Release odometer reset button.
Read the code on the odometer.

The gauges will sweep their full range and the odometer will count 0000000 to 9999999 if you release the button too soon.
 

Ok. Well my 05 tj is now doing alll that. Codes say miss fire Once was #1 cyl. Now #4. Did full tune up. O2 , crank sen, Nothing is helping. Little lost. Starting to think major as in compression loss , crack etc.....
 
Welcome to Jeepz.com. If you fear a major problem , do perform a compression check to verify loss of compression in any cylinder. Good place to start. Read the spark plugs. You want to know if any plug is fouled , I.E. , carbon , raw fuel , damaged porcelain or electrode , etc..
Check spark quality . A small flash from the plug is treated as a no spark which may be a bad ignition coil or not receiving full voltage. Check coil positive value for voltage reading.
A bad head gasket or cylinder head will result in loss of compression , burning coolant , engine oil burning in combustion chamber if seeping through a crack from topside. A compression check needs to be performed to evaluate or rule out this possibility. Determine if any fuel injectors are leaking raw fuel if any spark plugs are found to be saturated in raw fuel. I would say these items are a start in diagnostics first before any other checks are sought. Primarily . You want to know the engines condition in its ability to make compression to perform , fuel and spark and any electrical can be diagnosed next. You can have the best fuel injection pattern or spark quality but won't do any good if compression is lost. Hoping for the best , not the worst. Hope this helps .
 
What are all the codes you get?
P0XXXX????


Any other symptoms previous? Squealing sounds or shuttering?

Check fuel pressure.

What plugs were used? Brand and part number.

Where did you buy the I2's and CPS??

Check the rail connections and wires. Be sure none of the plug boots are cracked or damaged.
 

Mine has the same problem, have a 98 wrangler sport 5 inch lift and 33s, just put new exhaust, took o2 sensors out, was able to only save muffler, new air filter, it will start fine go down the road a little bit, it will bog rpms will jump up and down then it will pick back up and take off any idea?
 
2 problems I found, (1) If this occurs after 30min cool down, change front O2 sensor (also excess oil on intake can foul sensor and reduce fuel mph). (2) battery slides into computer harness disrupting input/output sensor readings/signals. Put 1" or thicker spacer on rear battery clamp to hold and push battery away from computer/harness, (got 6,644 positive responses to this)!

Hey ya'll.

With all the Jeep people in the know around here I am sure I went to the right place for guidance on my ride.

Here is my situation -

1997 Jeep Wrangler 4.0 137,000 mi.

It is strange but my problem is off and on. My Jeep sputters, loses accelation and makes a bubbling popping sound when I hit the gas (also my RPMs drop). Sometimes this is accompanied by my check engine light coming on. In the past year I have replaced my:

Cap, Rotor, plugs, crank sensor, fuel pump, thermostat, cat converter and transmission.

For example, this was happening really bad on and off, then it stopped for a day or two, I then drove over 500 miles through the White Mountains with NO problem, I come home and now this problem is back again and even worse (again off and on but more frequent).

I had Auto Zone hook my Jeep to a computer and it says my Oxygen sensor has an issue. Any opinions?

Could it be my oxygen sensor? If so which one? Or is it something else.
Has any one had this problem?
 
I am wondering how do you check the timing ive searched far and wide i have a 97 2.5 TJ and Blew a head gasket recently and it caused something to go wrong in the distributor so my cousin tried to put a new distributor in and it wouldnt run at all so he took the old distributor and replaced everything but one part and when i come up to running temp it starts to bogg down when it idles and when i try to accelerate it boggs down and once i get past the bogging it runs fine until i let it idel back down and it just repeats the process

could it be a hairline crack in the exhaust manifold or would it be a fuel problem we changed the o2 sensors the alternator and the battery out

i could realy use some help here
 

I seem to be having these same problems but mine occurred after I had my manifold gasket replaced now I have a miss and it barely climbs the mt I have looked and looked at several different forums and it seems people replace one thing after another and still have the problem anyone with a suggestion I would greatly appreciate it
 
Dconfer - you should start a NEW topic this is a zombie post just will not die - or go away.

Tell us year, engine etc, POST all codes.

FYI Autozone etal sell parts so their answer is buy buy buy.

THERE Is no code that says change a part.
 
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