94XJCherokee

-1997 Cherokee
-4.0
-Auto
-284,000

I was driving the other day at 60mph and all of a sudden the Jeep acted like it got put into neutral, engine reved real high and I had nothing from trans.

I let of the gas through it in neutral real quick and pulled over. Only gear I had left was first. Towed jeep home, checked trans fluid, bout a quart low. So topped it off.

Now I got first - third, no overdrive and also a book long list of CEL codes

-PO108 MAP sensor
-PO118 Engine coolant temp sensor
-PO121 TPS
-PO122 TPS
-PO123 TPS
And finaly the transmission code;
-PO700 Trans system malfunction

I am not too worried about the other codes, pretty self explanitory bout what they mean, but I had no CEL untill the trans acted up.

I know the PO700 usually goes along with the NSS code, so I took the NSS out last night and cleanded (it was crazy dirty) and no change

MY question is, could the TPS and MAP cause the trans to go all whacky? and If not HOW do I fix the PO700 code.

Thanks guys, looking forward to what you got to say. Appreciate it

tjwalker

The P0700 is kind of a generic code that relates to the transmission.

I would recommend you concentrate on the throttle position codes. The TPS is DIRECTLY involved with shifting characteristics of the AW4 transmission. Critical input signals at play here.

Get a new TPS installed. I buy my engine management sensors directly from the Jeep dealership for best reliability and longevity.

When you replace the TPS, clean the connector thoroughly with electrical contact cleaner and add a dab of dielectric grease to the connector before connecting.

Start with that, then clear all codes and see if any codes return and address them.

Good luck and keep us posted!

94XJCherokee

Thanks man, I was leaning to the TPS having something to do with it. I planned on getting one because the Jeep will not idle. Anyway thanks for the input man, Ill get back to you

tjwalker

The P0700 does sometimes accompany an NSS issue, but usually you get a P0705 with it.

With the TPS codes and the transmission symptoms, you really have to start with a fresh TPS.

You may have multiple issues, but the rule is to address them one at a time.

And the TPS codes rule here.

I also would refresh your engine grounds in the event that improper grounding is causing some gremlins here. Here is more.
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Grounds can be the root cause of many electrical gremlins. Refreshing grounds is NEVER a bad idea, and the investment of your time in this procedure is always well worth it!

You can't tell much of anything by looking at ground connections!! You must remove, scrape, clean until shiny the cable/wire ends and whatever they bolt to. Be sure to remove all paint from any ground connections.

Start with the one on the back corner of the head, and where it attaches to the firewall, as it deteriorates over time and is an area that makes it susceptible to damage. Best to replace that woven cable with a #4 or #2 gauge cable. You can attach the one end to the intake manifold if you would like.

Next go over to the engine dipstick tube stud. Remove the nut and clean the wire ends and scrape the block until shiny at the stud. Reattach tightly.

If you are so inclined, add at least a #6 cable from the negative terminal of your battery to one of the bolts on your radiator support.

94XJCherokee

All right I replaced the TPS then took the Jeep for a drive. It went through all the gears, still sifting a little wierd but went 1st - OD. First to second seemed normal, about 1500 rpm, but 3rd came a little late at about 3k, then OD normal.

I turned around at the end of the road and on the way back It wouldnt shift to over drive.

Any ideas? Replace MAP?

94XJCherokee

buuuuump....

tjwalker

The throttle position and the clockspring share grounds. Does your horn work? The horn is part of the clockspring circuit.

Have you performed a comprehensive inspection of the connector and all wiring associated with the TPS? The OBD system is pretty good at pointing you in the right direction and that direction is the TPS circuit.

http://www.justanswer.com/jeep/3itct...-replaced.html

The NSS is still a possibility with that overdrive situation, (cleaning is always recommended but does not guarantee full function if the problem is electrical) but I'd definitely focus on those TPS codes first.