Hesitates in 2nd gear and/or Sputters in 1st and 2nd

[greg92jeepxj]

Wow , when it rains , it pours . Sorry about the coil on plug , they're a little pricey for some makes . If the EVAP is off at idle and opens on cruise , it's probably ok but you'll want to dump all those dtc's as you probably are to monitor that . Real funny how an exhaust leak has such a dramatic effect to engine performance . No misfire logged is good of course . If your planning on getting to the manifold gasket ( that's enough work right there ) of course we're curious of the test drive to follow to see if the O2 is picking up the un metered air and is the problem .

 

[Bond--007]

Greg, I'll post back once the gasket is done. The plan for next weekend is the exhaust manifold gasket and running seafoam through the vacuum system to get some of the crap cleaned out. After seeing what the throttle body looked like before and after cleaning, I can imagine what the rest looks like

 

[greg92jeepxj]

Sounds like a plan . I know you got enough work in front of you so wishing you best of luck .
Im so used to my 4.0 liter that I forgot if the 2.5 has an EGR valve , the 4.0 chrysler dosen't. If yours does , just one more thing to check and clean . Swell .

 

[Bond--007]

Woohoo... (Cartwheels and backflips)...... lol

 

[JPNinPA]

I really should get one instead of borrowing it (damn truck went down tonight, #8 COP took a dump. Irony i still had the scanner....). As for the EVAP, still holding and no pending code. This again leads me to believe it was stored in there before I changed the solenoid out. The #3 misfire hasn't come back either. Again could have been before the plug, wire, rotor, cap change

When checking for leaks include the plugs as they are potential areas. Also if the exhaust manifold gasket bad this can be your vac leak. There could be exhaust in the intake.

For checking O2 sensors, I'd have to look again but they could read fine once warm but cause issues during startup.

 

[greg92jeepxj]

X2 on the integral intake/exhaust gasket. Unmetered air sucked into the intake causes lean condition and on an exhaust port will upset O2 readings as well. A tight seal of the manifold is a must for that little four to run good performance wise and not cause havoc with driveability issues with engine management pcm wise. Really no different with any engine but the four cylinder is a bit more critical with its smaller displacement and torque specs. It's likely to be key to the problem here. Yes , the threads on the spark plugs should be chased for better sealing. Agreed.

 

[Bond--007]

Should I use regular antisease on the threads of the plugs or something else?

 

[greg92jeepxj]

Should I use regular antisease on the threads of the plugs or something else?

I'm not personally aware of anything else but anti sieze compound for O2 sensors and spark plugs . That's all I use and always works for me . Actually , I use anti sieze on practically everything I take apart if I think that seizing or galling will be an issue. Heck , if I'm changing a washer on a sink I'll use it on the screw threads just so that it don't get stuck next time . I literally swear by anti sieze compound. Think I'll get some kick backs from permatex for promoting their product ? Lol
i realize the question is with regards to a good seal of the spark plugs in the cylinder head but as long as the threads are in good shape and the right plug is installed , taper or washer seal , whatever is called for , I personally never had an issue. Only time that's ever a problem is with bad threads .

 

[Bond--007]

Think I'll get some kick backs from permatex for promoting their product ?

LOL. doubt it

 

[JPNinPA]

Seating plugs can be an issue when you stop incerting due to dirt/carbon close to the cylinder. You could just go back to be sure all are tight. If you find one loose address the issues. I do not use anything on spark plugs and never have an issue.

On the O2:

Just make sure you buy oem

http://www.jeepforum.com/forum/f9/97-tj-sputter-stall-o2-sensor-612880/

 

[Dragon5126]

Here is a bit of advice... YES get the OBD reader! And here is why you put an OEM coil back in it. Rarely will an O2 sensor cause stumble. they will force the PCM into a default mode and you will end up running rich. this doesn't cause stumbling unless your plugs are fouling, but that will throw a hard code and fire off the cel. The reader will tell you the soft codes that don't. OFTEN a misfire will set a soft code, UNLESS it is constant and then it will fire the light with a hard code. Now my comment on the OEM coil. They are NOTORIOUS for thermal issues in both engines used in the 4 cylinder TJs. When my 06 started throwing misfire-cyl2 errors and the wires and plugs were fine, I put an MSD coil in and the problem disappeared. The OEM coils are bad news, they are only partially potted. The MSDs are 100% potted in thermal epoxy, both physically and thermally supporting the coils. AN Irony about the PCMs, Ive had to winch out on occasion (imagine that) and once, the person behind the wheel while I tramped in the mud and connected the cable and straps and operated the winch, didnt keep the engine idle up enough to benefit from the output of the alternator, and pulled voltages down, well we were shoveling mud with the hood and no I am NOT joking. The Winch did finally step on the throttle and ease out on the clutch pedal :twisted: so the one on the Front of the TJ could get enough juice and assistance to pull up and over the mud and out of the mud hole in the horse arena we were building. What does this have to do with this thread? It threw a hard code related to the Automatic transmission... You Did notice that I mentioned that the driver did have to ease out on the clutch, didn't you?

 

[Dragon5126]

Seating plugs can be an issue when you stop incerting due to dirt/carbon close to the cylinder. You could just go back to be sure all are tight. If you find one loose address the issues. I do not use anything on spark plugs and never have an issue.

On the O2:

Just make sure you buy oem

97 TJ sputter and stall - o2 sensor? - JeepForum.com

Don't buy Bosh O2 sensors for a Jeep Look for NTK... avoid OEM due to twice the price. The NTK last longer than OEM, and brand new Bosh tend to throw errors right away (if not sooner!) This is why people say buy OEM, most cheap parts store brands are made by Bosh. Go for the NTK (made by NGK)

 

[Dragon5126]

I agree on the antisieze. As for electrical issues it is made out of graphite which is conductive to begin with. you DO need to be careful when using it on some sensors. So make sure there is no warning not to with the sensors packaging. As for corporate endorsements... Dielectric grease, for almost all electrical connections outside the passenger compartment, antisieze for everything that will have to be changed ESPECIALLY LUG NUTS! non chlorinated brake cleaner for cleaning grease and oil off the engine and from around neglected spark plugs PB BLASTER BY THE GALLON! a subscription to Harbor Freight coupons... (especially for their polishing compound and cloth wheels... get a quarter sheet palm sander and wet/dry 320/400/600 grit sand paper for those plastic headlights, work through the grits then use the polishing compounds in the appropriate orders on the cloth wheels in a drill and you will bring those brownish lenses back to an optically clear surface. if the issue is on the inside as well put in higher wattage elements (bulbs) they will cause the inner coating to flake off in time.) Bottom lining it all your tools are only PART of what you need to work on your vehicle, and keep it running with out excess work.

 

[Dragon5126]

the O2 sensors have a 15 minute (approx.) warm up period before they start generating errors except for open voltage errors, that is the PCM reads infinite resistance across them when cold, which indicates that the sensor is open and bad, HOWEVER, this can also mean a connector or harness issue as well. so if you get this type of error (dont recall the codes off the top of my head, but they are obvious by the names), check the connection first.

 

[Dragon5126]

Greg, what is the easiest way to check vacuum leaks? I know I have one I can't find yet because the vents and floor doesn't work, just the defrost (I found where the vacuum hooks onto the intake, so now I need to trace it out)

got a CEEGUAR? Seriously! pull off a heavy line into the crank case (non carbureted engines) plug the other end and blow a heavy amount of smoke into the hose you just pulled and look for where it is coming out of the engine. If you are checking a carbureted engine you will also have to check the smaller lines going to the carb by pulling one of them and doing the same there since carbureted cars draw vacuum off the intake for carb operation, injected vehicles use a central system for vacuum that includes the crankcase which is why a bad pcv valve can really screw you up. When in doubt check crank case and manifold vacuum sources separately after all you DO have the whole cigar to burn... ( I always check both simply due to ruptured ear drums and I cant {keep it clean men} blow hard enough into the crank case to push smoke all the way through) BTW, ENGINE OFF!

 

[Bond--007]

Here is a bit of advice... YES get the OBD reader! And here is why you put an OEM coil back in it. Rarely will an O2 sensor cause stumble. they will force the PCM into a default mode and you will end up running rich. this doesn't cause stumbling unless your plugs are fouling, but that will throw a hard code and fire off the cel. The reader will tell you the soft codes that don't. OFTEN a misfire will set a soft code, UNLESS it is constant and then it will fire the light with a hard code. Now my comment on the OEM coil. They are NOTORIOUS for thermal issues in both engines used in the 4 cylinder TJs. When my 06 started throwing misfire-cyl2 errors and the wires and plugs were fine, I put an MSD coil in and the problem disappeared. The OEM coils are bad news, they are only partially potted. The MSDs are 100% potted in thermal epoxy, both physically and thermally supporting the coils. AN Irony about the PCMs, Ive had to winch out on occasion (imagine that) and once, the person behind the wheel while I tramped in the mud and connected the cable and straps and operated the winch, didnt keep the engine idle up enough to benefit from the output of the alternator, and pulled voltages down, well we were shoveling mud with the hood and no I am NOT joking. The Winch did finally step on the throttle and ease out on the clutch pedal :twisted: so the one on the Front of the TJ could get enough juice and assistance to pull up and over the mud and out of the mud hole in the horse arena we were building. What does this have to do with this thread? It threw a hard code related to the Automatic transmission... You Did notice that I mentioned that the driver did have to ease out on the clutch, didn't you?

The bad COP was on my truck, not the Jeep

 

[Bond--007]

UPDATE: I decided to data log again this morning on my way to work. One piece of info I noticed was the ST FTRM11 reading from the scanner. Most of the time it would fluctuate around 0 with a +/- 3. On the interstate I noticed the value dropped to -35.3. Is this something to be concerned about?

 

[JPNinPA]

UPDATE: I decided to data log again this morning on my way to work. One piece of info I noticed was the ST FTRM11 reading from the scanner. Most of the time it would fluctuate around 0 with a +/- 3. On the interstate I noticed the value dropped to -35.3. Is this something to be concerned about?

Have you corrected the exhaust and intake leak?

 

[greg92jeepxj]

Not being personally advanced in such measurements , I couldn't say what relevance these shot trim and long trim fuel readings mean to us but percent is more commonly found in most manuals and what is mostly used as a gauge of fuel trim. As JPNinPA asks , with regards to the intake/exhaust repair , that will have significant effect on the engine management (pcm) with oxygen sensor readings since the leak is creating an unstable condition affecting the PCM's ability to accurately achieve an optimum fuel/air ratio . Simply put , that leak is reaking havoc on your engines performance and the PCM is trying to compensate for it. Once corrected , the fuel trim should be more stable and O2 feedback readings should more normal and meaningful. Short trim and long trim calculations do make interesting reading however.

 

[Bond--007]

Have you corrected the exhaust and intake leak?

Not being personally advanced in such measurements , I couldn't say what relevance these shot trim and long trim fuel readings mean to us but percent is more commonly found in most manuals and what is mostly used as a gauge of fuel trim. As JPNinPA asks , with regards to the intake/exhaust repair , that will have significant effect on the engine management (pcm) with oxygen sensor readings since the leak is creating an unstable condition affecting the PCM's ability to accurately achieve an optimum fuel/air ratio . Simply put , that leak is reaking havoc on your engines performance and the PCM is trying to compensate for it. Once corrected , the fuel trim should be more stable and O2 feedback readings should more normal and meaningful. Short trim and long trim calculations do make interesting reading however.

We are changing the manifold gasket and checking for vacuum leaks this Sunday. When I was data logging and saw the negative number, I was thinking I might have something else going bad in addition to the current issue (wouldn't even surprise me)