overdrive in and out(headache)

[opel]

I see in my searches this has been beat to death but I have tried about everything. I'll start a list. Two new tps's. I checked this one for voltage. . 84 at idle 3. 63 wide open, smooth all the way. New tran temp switch,Two new transmissions, wiring went through. no codes, all grounds cleaned, new cable was adjusted by trans shop,all connections cleaned and di-electric greased,new distance speed sensor,everything thing reads good going down the road with Genesis scan tool hooked up,Snap on showed the same,both switch and sender new in the manifold by the heat screens, probably missed some but anything to do with the trany has replaced excet pcm which i am confused on. When i go into the module to see what it is and get specs it says the following.

#5602568-7

5. 9L

canadian /federal

1991

diesel

rearwheel drive

auto trans

truck

NON TURBO I did'nt know of any but mine is definatly turbo!!

seq mpi ( I assume sequentil multi-port injection) ITS A DIESEL!!

 

[BushWakr - RIP]

What kind of shape is the crank sensor in??? They are mounted at about the 11:00 position, just above the balancer. The wire leads down the front of the gear cover just beside the alternator.



That sensor has a gap requirement of . 049-. 051". It should be set using a non-magnetic feeler gauge and care should be taken to assure the "notches" in the balancer are not near/under the sensor tip.



bob.

 

[opel]

Well, I double checked and it does not have a crank sensor. I was thinking they did not start that until 92 but I could very well be wrong.

 

[Philip]

If you have an overdrive trans you should have a crank sensor like BW said. It is painted black the same as the engine is. The wires going to it run with the wiring going to the TPS. Where the wires branch off to the TPS. The crank sensor wires are the ones going over by the upper raditor hose connection.

 

[opel]

This isnt good. I have no crank sensor! It is not in my manual either. I can find it on the 92 but not the 91. Uh OH. There is no wires at all going to the crank. I traced the tps and it just goes right into the harness by the fuel filter no other wires. Now what. Leave it to me to have the wierd truck!

 

[Copterdoc]

overdrive fix

You could go to a manual push button to activate your overdrive. Me and a friend have been running ours this way for a while(me 2years, Him 3 years) with great results. Go to the od solenoid on the back of the transmission. Cut the two wires about 6 inchs up from the plug. Put a terminal on the ground wire and put it under a transmission pan bolt. Run a 12 volt wire from the fuse box to the hot wire with a switch inline and you have push button O/D. Take the TPS off of your pump and throw it as far as you can. copterdoc





P. S. I am thinking about converting mine from a dash switch to a Head light dimmer switch on the froor.

 

[opel]

Now that s an idea!

 

["Mad Max"]

od switch

I just finished installing a column-mount gear shift lever (for the auto) from a 2nd gen Ram that 'bolted' right into place, but it has the od switch in the tip of the lever - one wire to ground, the other to the orange/white wire on the back of the original switch, and presto! Works perfectly.

On my TPS - remove the two allen bolts that hold it down, and then remove the two steel sleeves inside the bolt holes, re-install with little washers under the bolt heads, and turn the TPS as far counter clockwise as it will go. The extra 'adjustment' by not having the sleeves seemed to do the trick. Don't know what the voltage is now, but OD kicks on nice and hard every time, even on a hill, and I can turn it off if I want to stay in 3rd a while.

I'm also planning to use a foot dimmer, but mine will be for my high beams. The column high beam lever function will be rewired to work a set of fog lights... ...

Here's a pic of the TPS installed - note the orientation - works for me...

- S

#ad

 

[soslow91]

I have a late 91 auto no crank sensor also. PCM is screwed intermitant speedo and no OD I have a toggle switch on mine.

 

[RGT]

I put a switch to manually engage mine aslo, for other reasons, I tapped into the wire at the connector on the back of the engine rather than splicing underneath' works great.

 

[cerberusiam]

Opel, what exactly is the OD doing? Late shifts under hard throttle? Intermittent in and out at steady speeds? Looks like you replaced everything but the PCM and that could be the problem. Did you pull the PCM connector clean and grease it? The PCM is the ultimate control for the OD. It uses the feeds from TPS, speed sensor, and trans temp sensor to determine shifting. Testing on mine indicated the crank sensor had no effect on OD shift but that may vary dpending on PCM. I believe DC used the same PCM on the gassers and diesels so the options list can be misleading.



The other component that could be a problem is the OD solenoid in the trans itself. If it is not working correctly the PCM could sending an engage signal correctly but it won't be diagnosed. One other thing could just be noise interference in the wiring harness. Some have cured the flaky OD shift with a filter in the TPS harness. The mystery switch method works great when nothin else does. You could also go to an aftermarket controller for the OD. Spendy but works. Good luck.

 

[SClements]

My 91. 5 doesn't have a crank sensor either. The vibration damper has the grooves in it though. They must have been getting ready for it.