TPS saga continued, Gremlin identified, maybe?

[Guest wally888]

Finally the TP Sensor started working properly. Thursday I started the car several times, idled correctly each time. Friday I repeated, then started on a 25 mile trip.<BR> Oops! One mile into the journey, "Engine Elec. Prob. Detected."<BR> As I drove the 25 miles this warning appeared 5 or 6 times but cleared itself each time before returning. Each time it appeared I would enter diagnostics. If I was quick I could catch both history and current<BR>code but about 3 times I got only history.<BR> After parking w/ the engine running, I was able, on several occasions to set and clear the code by tapping the gas pedal. Hope Tom W. agrees this is an internal TPS problem? I ordered one and also a Cruise Control Switch. What is next!

[Guest]

Wally,<P>Still sounds like a bad tps sencer. The tps is just a potentiometer. It has a coil of thin resistance wire with a contact that moves back and forth on the wire. The wire might have a bad spot or a dirty contact in the sencer. I was looking at mine the other day and would say it would be easiest to pull the throttle body off the intake to do the tps. You probibly don't have to unhook everything. Just enough to pull it and rotate to get to the sencer. If the screws don't want to come out easy heat them up with a very small amount. Not glowing hot but just warm. Sometimes a loctite is used that must be heated before removal or the screw will break. Ford is bad for this but a few GM's are like this too. Or a screw may want to sieze in the allumimn. I would not use loctite for putting it back together. Anti-sieze would not hurt but is not needed. The sencer does not go strait on the t-body. It should be put on so the throttle pin lines up inside the sencer and rotated a bit so the screws line up. Plug it in and double check the operation and readings with the tps readout on the cars computer before reinstalling. If nessisary tweek the sencer to one side of the screw holes to obtain the right (check the book) idle tps voltage.<P>Tom

[Guest wally888]

Thanks Tom,<BR> Will let you know how this turns out. Is it easy to disassemble and expose potentiometer?

[Guest]

without knowing how many miles you have on your reatta already, i'm standing on a ledge, but i'm a firm believer in replacing sensors (with acdelco parts) rather than dissembling them and trying to repair them. To me, its not worth my time and fuss, I would rather just replace and be done with it.<P>Just today, I had a miss. I was anticipating all sorts of small evils with the car (my 88 has over 176K on the clock).<P>First, I disconnected the Idle control motor. Then one by one, I disconnected each fuel injector until I found the one that didn?t cause the rpm?s to drop. Thus, finding the cylinder that wasn?t firing. Now, was it a problem with spark or fuel? I pulled the spark plug but it looked good. Then I grounded out the plug and cranked the motor only to find no spark. I switched the plug wire and viola! Spark! And no more miss, once the replacement plug wire and spark plug was installed.<P>My spark plug wires are Acdelco parts, and have only been on the car for 2 years, so I replaced the one, instead of the whole set. Closer inspection revealed a break in continuity from coil end to plug end, but no physical cause on the outer insulating jacket of the wire.<P>I saved myself the hassles of dropping the car off, dealing with the mechanic, paying for a computer diagnosis, parts and installation of a $6 wire.<P>The factory Manual for the reatta has been invaluable for solving ?simple? problems with the car. I would recommend prowling around ebay for one, or just asking around here for someone to sell one, or point in the general direction. The manual has step by step troubleshooting steps for diagnosing problems like TPS, or anything having to do with drivability, or the entire car.<P>If the repair seems to over anyone?s head, then by all means, take the car to a reputable repair shop. But I?ve found most of the troubleshooting charts easier to understand than my tax forms!<P>(after rereading this post, I?ve surprised myself at how many words I can use without taking a breath)<BR>

[Guest]

If you do decide to pull the throttle body, be sure to drain the coolant down a little as there are steel coolant lines atached to the bottom of the throttle body and they are a real chore to get them out without destroying them. Twisting the T'Body for access is not an option.<P>------------------<BR>Hal, btk@vbe.com

[Guest kennyw]

WALLY888,<BR> seems that you have two different problems. You didn't state the first one. I would expect [poor idle], Or motor stoping, because you think the IPS sencer is bad. The second is prabably another sencer problem. Electrical problem detected. The oil pressure sencer will cause this warning to appear. Keep the gages screen on. Watch the oil pressure. If the sencer is bad and the oil gauge goes up to 155-lb pressure the trouble [light] will appear and go off when the pressure goes down. That is why playing with the gas pedel can sometime remove the warning. The motor does not have 155-lb pressure, the sencer is just reading wrong. Change it or put up with it, your choice. It won't hurt anything............

[Guest wally888]

Happy to report the used TPS that Jim sold me is installed and cured my problem. Well not mine, the car's.<BR> TPS was off in 10 minutes (removed the rocker arm vent pipe on one end, used offset screwdriver and(don't shudder) common pliars.<BR>Took a while longer to install but no adjustment necessary. Read 0.42 before and after tightning. Idles great. Thanks to all.<BR>Will install steering column, Cruise Switch next.<BR> BTW. Appears the 89 switch is held in by a screw, maybe some model years are not. My 89 Manual mentions no screw, just pull out.