CEL 126 & weird tranny shifts

[Pitchblack98]

I just got a 95 240sx over the weekend. Its an automatic and I've yet to determine if its a Base or SE... lol... It comes up as SE on carfax, but only have 4 lugs. It's also fully loaded leather, power everything, sunroof, etc... It's pushing 153k miles. I picked it up for $3000 cash. Not too bad.

Now on to my question. I washed it tonight and cleaned it up under the hood. Before I washed it it ran great. After washing it the transmission just went crazy. It wouldnt shift out of first until it got close to redline and when it did shift it would break the wheels loose it shifted so hard. It wouldn't shift again until it got close to redline and I didn't have enough road to see if it would shift into overdrive at redline. lol... I also notice when I let off the gas the rpms would drop down to idle speed like I had pushed in a clutch then would rev way back up before it would start to accelerate again when I got back on the gas.

At first I had no CEL or anything. I pulled over and a parking lot and shut it down for a few minutes to see if maybe it would reset itself and go back normal. When starting it back up the Overdrive light would flash on the dash and shortly after that the CEL light came on. I pulled the codes and got 34 (knock sensor) and 126 (throttle position sensor). I went out and unplugged the TPS and blew out the connectors to get any water out that may have gotten in there. I also blew out all the other electrical connectors that I could see and get to pretty easily.

After that I went for another ride. When I first started it the O/D light flashed again, but the CEL didn't come back. This time it ran normal and felt like it did before I washed it. I shut it off again and then started it again and this time all the lights went off like normal with no flashing.

I imagine the TPS code caused the transmission to freak out, but figured I would ask you guys before I come to any conclusions. Should I be worried and start looking for another transmission or do you guys think this is just a fluke cause some water got into something it shouldnt have?

Let me know! Thanks in advance!

[Dream240]

Water under the hood is bad. Hence the hood's sole purpose. DON'T SPARY WATER ALL OVER THE ENGINE ANYMORE.

Get it steam cleaned if it's that bad, other wise brake clean for oil build up and a wash cloth and bucket for the dirt spots.

You need to have the codes cleared now. Go to the dealer and pay them for your mistake.

[Pitchblack98]

Water under the hood is bad. Hence the hood's sole purpose. DON'T SPARY WATER ALL OVER THE ENGINE ANYMORE.

Get it steam cleaned if it's that bad, other wise brake clean for oil build up and a wash cloth and bucket for the dirt spots.

You need to have the codes cleared now. Go to the dealer and pay them for your mistake.

I didn't spray the motor with water and don't recall saying that in my original post. Maybe you should read it slower next time. I'm a professional detailer part time and if I needed to spray off the motor I would of covered all the electrical connections. I did spray off the bottom of the car and cleaned out the wheels wells pretty good. My only guess was something got wet while I was cleaning underneath or in the wheel wells.

I already cleared the codes. I'm not an idiot when it comes to cars. I can throw around a wrench and have just as much if not more experience than a good majority on this board. This is my first 240 and figured I would ask about it since a search didn't point me in the direction I was looking for.

So your jackass comments are apprecaited, but no help. Thanks.

[Dream240]

I didn't spray the motor with water and don't recall saying that in my original post. Maybe you should read it slower next time. I'm a professional detailer part time and if I needed to spray off the motor I would of covered all the electrical connections. I did spray off the bottom of the car and cleaned out the wheels wells pretty good. My only guess was something got wet while I was cleaning underneath or in the wheel wells.

Okay so first you say you didn't spray the motor(it's called an engine genius) then you say you got underneath and sprayed the undercarriage I'm assuming with water? And how is this not getting transmission basically all wet?

It's really not that hard to expain so try and keep up, you bought a car, cleaned it and sprayed water all around, then transmission started acting up. You pulled TPS and some others and cleaned out any water or moisture, car ran better. YOU GOT SOMETHING WET YOU WEREN'T SUPPOSE TO IDIOT. Since you're such a car know it all why even bother coming on here to ask a stupid question you already seem to know the answer to?

And the codes will still flash after due to computer memory. But you should have already known that since you have the know how to clear codes.

Stop wasting my time showing off your knowledge of cars and start posting to help the countless newbies that are drowning in there own stupidity.

done.

[Pitchblack98]

lol you must be having a bad day or something... dunno...

As for getting the tranny wet, if you have found a way to drive in the rain without getting your undercarriage wet then congratulation. Considering the car has been driven in the rain for 12 years now, water underneath it would of killed it a long time ago. In colorado you have to wash the bottom and wheels wells of your vehicles. The magchloride they use on the roads will cause rust and eat right thru your chasis in a matter of months if not cleaned off. So I imagine you must roll under your car with a rag and wipe it all down by hand. Sounds like a very effective way to clean an undercarriage.

Also I don't seem to see any showing off of my car knowledge at all. You posted like I was a complete idiot when it comes to cars and I just stated I have a great deal of experience with working on and modding vehicles. Again read my posts a little slower next time and you might understand them better.

The reason I posted my question was to see if anyone else had an experience simular to the symptoms I was having and maybe what their outcome was. See as you have never been in a situation like this, your posts in this thread are useless and wasting everyones time include yours and mine.

As soon as I become more familuar with my 240 I will be more than happy to help out others asking questions. Right now I would be wasting their time trying to answer questions for them since I dont know the car quite yet. I'm not hear to waste anyones time, just hear to learn out the car and have fun with it.

Sorry if I offended you in some what or another, but your comments aren't helping anyone out.

[Dream240]

Okay well you seem to be misunderstanding me. i read your posts perfectly fine, you said you cleaned the undercarraige, washed the car, and cleaned out the engine bay with something. I'm assuming you washed the car first, with the hood closed then proceeded to spray the undercarraige with the hose in hand. then finished with popping the hood and spraying, wiping, scrubbing, or whatever you did to the engine bay.

It's not hard to get water up inside the engine bay from underneath, especially with a pressure spray nozzle. What I meant by getting the tranny wet was that you either managed to spray enough water under the car to soak the upper front portion of the engine where those electrical connectors are, or your method for detailing the engine bay is at fault. I meant to say the engine not tranny. Either way, again, you got water/moisture where you weren't supposed to.

The magchloride they use on the roads will cause rust and eat right thru your chasis in a matter of months if not cleaned off. So I imagine you must roll under your car with a rag and wipe it all down by hand. Sounds like a very effective way to clean an undercarriage

I don't live in a mountain area so I don't have any reason to clean under my car daily.

I already cleared the codes. I'm not an idiot when it comes to cars. I can throw around a wrench and have just as much if not more experience than a good majority on this board. This is my first 240 and figured I would ask about it since a search didn't point me in the direction I was looking for.


How do you figure this isn't bragging? You can't expect to come on here and have everyone take your word on your "extensive knowledge". Prove it by not starting needless threads that you start, diagnose, and solve all in the first post.

As far as offending me, no not at all. I'm simply pointing out that this thread really isn't necessary. You seem to possess a fair understanding of cars, whether it's a 240 or a Ford Festiva, they all operate under the same principals. And since you say you couldn't find any search results on this problem that should tell you that you have nothing to worry about.

What you need to be doing is sourcing out a tranny swap to make it a 5-speed and forget about the auto tranny altogether.

If my posts come off as rude, hey it's Zilvia. Welcome. :)

GL

[Pitchblack98]

lol... Its all good. Nothing like a good argument to be welcomed to the site.

I am in the process of finding a nice front clip with a SR and tranny to do the swap. Its not in my budget to do it just yet, but soon.

My wife got rearended at a stop light by some idiot going 55 mph (atleast thats what the cops estimated his speed at). They totalled her car considering they had to cut the door off of it so she could get out. I bought this car as a daily driver to get back and forth to work so she could drive my Frontier for the time being. As soon as we get finished fighting with the insurance company and get paid for all this crap she is getting a new car. Thats when my 240 goes into the garage and gets swapped. I can't have any down time with it at the moment, but as soon as I can drive my truck again and my wife has her own car, its on!

[aradapilot]

well that was an interesting read, heh

I'm currently having the exact same problem, to the letter, in a '90 hatch/single slammer. I had been driving through a...well, a monsoon, basically, lots of flooding...and my camshaft snapped in half. Cursed a lot thinking about hydrolock until I ripped the head apart and found out that everything else was fine and it was just a fluke thing. So, threw in a new cam, and now I'm having that same shifting problem. I originally thought it was the rev sensor, they tend to fail in 240s, so I disconnected that last night - no luck. Tried without the kickdown, jeg, still no luck. Had to get to bed - busy night and work early this morning - so I'm going to check out the tps and vss when I have a spare moment...I did have the tps disconnected for the timing work, and it may have gotten wet even though I 656'd it to death before reconnecting...or maybe in the original heavy rainstorm it was damaged.

Never checked tps or vss for voltages - anyone know where to test/expected values? for vss I'd have to test while moving so prolly hook something into the ATCU.

[Dream240]

Download an FSM for your year car (yes they're on this forum and many other places) search for it, hell even google.

Check the "EF & EC" section under pages EF&EC-102 for the VSS, and EF&EC-121 for the TPS. It'll give you all the correct readings you should get and how to get them.

Really all you need is a voltmeter and some patience.

GL

[aradapilot]

It's the TPS. was throwing 2.68V at closed throttle as opposed to the 0.4 expected. Just got a replacement, gonna swap it in a little later, I'm tired as hell.
And driving with the bad tps disconnected was fine. Obviously it shifted based on the charts in the fsm rather than pedal pressure, but otherwise performed beautifully.

[roycenagger]

Dang, I wash my engine and undercarriage about once every two months at the car wash. I've owned one of my 240s 17 yrs now. I just don't spray directly at the connectors, but they do get wet.
As a matter of fact, I've done this with every vehicle I've owned since 1978.
But of course, in the old days, getting the distributor wet caused many of no starts.

Just an FYI.

-Royce