P1860 P0753 P0758 Transmission won't shift

Hi Everyone,

I was driving home from work last week and my car was fine until I went to go park it. I heard a weird noise and then it went bad. My car goes in reverse just fine but when in drive (going forward) it seems to stay in 3rd gear "limp mode". I scanned the car and got 3 codes:

P1860: TCC PWM Solenoid Circuit
P0753: Shift Solenoid A Electrical
P0758: Shift Solenoid B Electrical

So I drove it around a block a few times, if I put the car in 1st, it will start in 2nd. Then if I shift to D from 1st, then the car will shift to 3rd (but no overdrive). I guess the car is "manually shifting" ok. It is weird to get 3 codes at once saying 3 solenoids are bad. I don't think the transmission is bad, I can manually shift and get the car up 60ish just fine. The car seems to be running hotter than usual too. Also ATF is full and red I do see bubbles on the dipstick.

I did a search on line a came across this:

http://www.grandprixforums.net/threads/5256-P0753-P0758-P1860-1-2-and-2-3-shift-solenoid-and-TCC-pulse-width-modulator-errors

It seems my conditions are exactly like this guy's conditions but his is a Grand Prix. Any suggestions and/or help on this would be awesome. Thanks!!

All 3 of those codes at once leads me to believe that you lost the voltage supply circuit for the trans solenoids somehow. I highly doubt that all 3 solenoids are bad.

First thing you need to check is the OXY SENSOR fuse in the IP Fuse Block. It's a 20A fuse. Yes, I know it says OXY Sensor, but that's what it is. You also need to check the CLNG FAN fuse. It's a 10A also in the IP Fuse Block.

There are a few splices and/or connectors in between the fuse and the trans. If all fuses test good, it's possible you have a bad splice or a harness rubbed through somewhere.

Thanks. i will check the fuses and report back.

i checked the 2 fuses like you said and the fuse to the oxygen sensor was blown. i replaced it, cleared the codes and transmission shift like normal. Thank you, thank you, thank you.

brettfavreisamonster wrote:

i checked the 2 fuses like you said and the fuse to the oxygen sensor was blown. i replaced it, cleared the codes and transmission shift like normal. Thank you, thank you, thank you.

Not a problem! Hopefully the fuse just got "old" and there isn't anything that'll cause it to pop again.

Looks like the problem keeps happening. So something is causing the fuse to pop.

brettfavreisamonster wrote:

Looks like the problem keeps happening. So something is causing the fuse to pop.

Well that sucks. Time to find out where the power wire is touching ground. Start following the trans harness until you find where it's rubbed through.

Abaddon wrote:

brettfavreisamonster wrote:

Looks like the problem keeps happening. So something is causing the fuse to pop.

Well that sucks. Time to find out where the power wire is touching ground. Start following the trans harness until you find where it's rubbed through.

My guess but it is only a guess is somewhere near the exh manifold. Also part of the guess is that due to prior servicing the wires did not get re-anchored to where they were supposed to be, like after a long-ago R&R of the transmission. Put the car in park, open the hood, and blip the throttle while watching the engine. What happens to the wires? What shape are your motor mounts in (does the engine rock a lot in the cradle?) If never replaced they are prob'ly shot.

Check it out & Please report back.

albertj wrote:

Abaddon wrote:

brettfavreisamonster wrote:

Looks like the problem keeps happening. So something is causing the fuse to pop.

Well that sucks. Time to find out where the power wire is touching ground. Start following the trans harness until you find where it's rubbed through.

My guess but it is only a guess is somewhere near the exh manifold. Also part of the guess is that due to prior servicing the wires did not get re-anchored to where they were supposed to be, like after a long-ago R&R of the transmission.  Put the car in park, open the hood, and blip the throttle while watching the engine.  What happens to the wires?  What shape are your motor mounts in (does the engine rock a lot in the cradle?)   If never replaced they are prob'ly shot.

Check it out & Please report back.

I will have time to check the wires this friday and will report back. My rear motor mount was replaced last year. I had them filled too. The motor doesn't move more than usual.

Some side notes that may or may not be related. My new sway bar is rubbing badly on the exhaust. My ac fans in the car sometimes stop but if i push against the carpet by the front passenger kick panel it works again. Cant seem to get ride of a cam sensor code p0341.

brettfavreisamonster wrote:

Some side notes that may or may not be related. My new sway bar is rubbing badly on the exhaust. My ac fans in the car sometimes stop but if i push against the carpet by the front passenger kick panel it works again. Cant seem to get ride of a cam sensor code p0341.

AC fans? Like big cooling fans or blower motor?

brettfavreisamonster wrote:

Some side notes that may or may not be related. My new sway bar is rubbing badly on the exhaust. My ac fans in the car sometimes stop but if i push against the carpet by the front passenger kick panel it works again. Cant seem to get ride of a cam sensor code p0341.

Sway bar rub: my guess is your motor mounts are wack

AC fan in the car: check the wiring to the fan, the fan drops out if you unbolt it and go from there

Cam sensor code: check the wiring at the ignition module (the thing the coil sit on) but its as likely you just need to replace the cam sensor. It is unlikely that the cam magnet fell off or some nonsense like that.

brettfavreisamonster wrote:

Some side notes that may or may not be related. My new sway bar is rubbing badly on the exhaust. My ac fans in the car sometimes stop but if i push against the carpet by the front passenger kick panel it works again. Cant seem to get ride of a cam sensor code p0341.

The cam sensor code is almost always a bad wire right at the firewall engine harness connection. The wire is at the bottom left corner of the harness. There is a cover that must be removed to see the wires. In my case., the wire was broken internally but would make contact at times and not at others, triggering the code. With a Tech2 scan tool connected, I was able to watch the cam sensor signal drop out when I touched the wire. This is a very common problem for some reason. Maybe the wire is stressed for some reason. See the last post in this thread,

https://rivperformance.editboard.com/t4703p200-faq-p0341-camshaft-position-sensor-cam-sensor-timing-chain?highlight=cam+sensor+code

I cut and pasted the pictures from earlier in the thread.

Abaddon wrote:

brettfavreisamonster wrote:

Some side notes that may or may not be related. My new sway bar is rubbing badly on the exhaust. My ac fans in the car sometimes stop but if i push against the carpet by the front passenger kick panel it works again. Cant seem to get ride of a cam sensor code p0341.

AC fans? Like big cooling fans or blower motor?

blower motor. it turns off. so i would ask the passenger to step on the carpet near the kick panel and it would start working again. happens more often when it is hot out.

albertj wrote:

brettfavreisamonster wrote:

Some side notes that may or may not be related. My new sway bar is rubbing badly on the exhaust. My ac fans in the car sometimes stop but if i push against the carpet by the front passenger kick panel it works again. Cant seem to get ride of a cam sensor code p0341.

Sway bar rub:  my guess is your motor mounts are wack

AC fan in the car: check the wiring to the fan, the fan drops out if you unbolt it and go from there

Cam sensor code: check the wiring at the ignition module (the thing the coil sit on) but its as likely you just need to replace the cam sensor.  It is unlikely that the cam magnet fell off or some nonsense like that.

the sway bar didn't rub before i put in the bigger one. it's the blower motor in the car that stops. i will check all the wires this Friday. i tried 3 different cam sensors and still the same code. i rotated the motor to see if the mag is still in there and it is. this happened right after i did a water pump change.

brettfavreisamonster wrote:

albertj wrote:

brettfavreisamonster wrote:

Some side notes that may or may not be related. My new sway bar is rubbing badly on the exhaust. My ac fans in the car sometimes stop but if i push against the carpet by the front passenger kick panel it works again. Cant seem to get ride of a cam sensor code p0341.

Sway bar rub:  my guess is your motor mounts are wack

AC fan in the car: check the wiring to the fan, the fan drops out if you unbolt it and go from there

Cam sensor code: check the wiring at the ignition module (the thing the coil sit on) but its as likely you just need to replace the cam sensor.  It is unlikely that the cam magnet fell off or some nonsense like that.

the sway bar didn't rub before i put in the bigger one. it's the blower motor in the car that stops. i will check all the wires this Friday. i tried 3 different cam sensors and still the same code. i rotated the motor to see if the mag is still in there and it is. this happened right after i did a water pump change.

There was an earlier post about the wiring to the cam sensor, check it out.

brettfavreisamonster wrote:

this happened right after i did a water pump change.

Same thing happened to me.  Bet it is the wire up near the firewall harness connector.

Hello guys, sorry for the delayed result. Finally got the chance to really get under the car. it turns out to be the rear o2 sensor. The wires are sliced by the heat shield covering it. Must have happened when i took off part of the exhaust to do my sway bar. I didnt support the exhaust and just let it hung there. took the shield off for now so everything should be ok until i get another rear o2 sensor.

this car has had a different problem every week. Heater hose blew, power steering pump broke, front right brake line blew, and cracked radiator. Each happening right after the other got fixed. so i finally got a chance to fixed this blown fuse issue. been manually shifting the car every time the fuse pops.

Thanks again for all you help!!

LARRY70GS wrote:

brettfavreisamonster wrote:

Some side notes that may or may not be related. My new sway bar is rubbing badly on the exhaust. My ac fans in the car sometimes stop but if i push against the carpet by the front passenger kick panel it works again. Cant seem to get ride of a cam sensor code p0341.

The cam sensor code is almost always a bad wire right at the firewall engine harness connection.  The wire is at the bottom left corner of the harness.  There is a cover that must be removed to see the wires.  In my case., the wire was broken internally but would make contact at times and not at others, triggering the code.  With a Tech2 scan tool connected, I was able to watch the cam sensor signal drop out when I touched the wire.  This is a very common problem for some reason.  Maybe the wire is stressed for some reason.  See the last post in this thread,

https://rivperformance.editboard.com/t4703p200-faq-p0341-camshaft-position-sensor-cam-sensor-timing-chain?highlight=cam+sensor+code

I cut and pasted the pictures from earlier in the thread.

I heard it was a common problem because of some wire (lower bidder) GM got that was copper but not made to avoid work-hardening... which makes it brittle and it breaks inside the insulation eventually from vibration, not far from where the connector is swaged onto the wire. I don't have proof of that so no nastygrams to GM.

brettfavreisamonster wrote:

Hello guys, sorry for the delayed result. Finally got the chance to really get under the car. it turns out to be the rear o2 sensor. The wires are sliced by the heat shield covering it. Must have happened when i took off part of the exhaust to do my sway bar. I didnt support the exhaust and just let it hung there. took the shield off for now so everything should be ok until i get another rear o2 sensor.

this car has had a different problem every week. Heater hose blew, power steering pump broke, front right brake line blew, and cracked radiator. Each happening right after the other got fixed. so i finally got a chance to fixed this blown fuse issue. been manually shifting the car every time the fuse pops.

Thanks again for all you help!!

Given the age of your car check the firewall connector anyway. Seriously. I remember leaning on Larry 'til he checked his, he posted a nice explanation you can find elsewhere on this site.

I will check that wire and report back. Thanks.

brettfavreisamonster wrote:

I will check that wire and report back. Thanks.

...yeah the point is to eliminate the easy-to-detect stuff that others have uncovered over the years.  The busted wire on the ignition module was on a lot of the 96s and a few of the 97s.  I do not remember any 98s with that issue. So if you check it now you can scratch that off the list hopefully -

Here is a sidebar note you might find interesting.  On my 98 I've checked the wires into the ignition module several times.  Never found a busted conductor.  I have replaced the ignition module once, and there is one coil pack, the 1-4, that I replaced twice -- once when it went bad while traveling on a long road trip apparently because a spark plug cable wore out. The SC Riv has a very high energy ignition;  a loose/bad spark plug cable will make the associated coil blow itself out, apparently they can get loose as the metal fatigues in or ablates from the terminals due to the high energy spark or the conductor opens at some physical stress point that has ablated.  I later replaced the replacement coil with a junkyard coil when I discovered that the replacement coil was for a NA riv (those coils are a lower spec) as I was troubleshooting to try to cure a mild lope.  Diagnosis:  the primary winding on the replacement coil was way different than on the other 2.  So I got a set of junkyard coils off an SC Park Ave, measured them - OK they were the same as the remaining OE coils.  So I put one of the SC PA coils on in place of the replacement, and wha-la, lope was gone. Surprised me that there was that much difference in the coils.  

In practical terms, this means the only coils you really want to use on the SC Riv are Delco D576.  *All* the other coils shown on RockAuto.com in the listing for  '98 SC Riv are, in fact, the NA spec coil.  They will work but they do not put out the same spark as the D576 and if you're tuning, or just picky, you'll be able to tell the difference.  You're actually better off with a junkyard coil off an SC engine than with a new coil, unless the new coil is the Delco D576.   One way to get them inexpensively is to go to a larger pick-n-pull and pull them off of any  3800 SC Series II, being careful to note if they're original or replacements. The Park Avenues are not driven all that hard and there are more of them hint hint.  You can look at the pictures on Rockauto.com before you go to see what the replacements look like.   Measure them with your ohmmeter and match up coils into sets based on the  primary resistance and the secondary resistance.

Albertj