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1990 Plymouth Other Repair Question


Topics covered: Sensor, Engine, Battery.
Mileage: No information provided.

Asked on July 8, 2008

1990 Other Plymouth Models TPS values


I recently purchased a 90 Laser at auction. The engine runs great, trans is nice, everything is OK, but the engine light is on, and I need to turn it off for emission purposes. The code reader shows
13, 15, 21, and 25. I have replaced the temp sensor, tried a second intake sensor for the Baro, air temp codes. Running the ohms test on the TPS shows a lo read of 234 ohms, and hi at 5600. The book says low should be 1100, and high 5600. Is the sensor bad?
Avatar Asked by OldLaser

Answer

Replied on July 8, 2008

I don't have the ohm spec, but it looks out to me.

Mitchell shows the voltage between .48 and .52 with this procedure:


http://www.2carpros.com/forum/automotive_pictures/30961_laz_1.jpg

Tiny Answered by Service Writer (expert)
9,955 answers provided
Replied on July 8, 2008

Thanks for the reply. The Haynes manual I have shows the same (4.8 - 5.2) signal voltage, and that reads correct on the multimeter. At 4.92 on the scale at the harness connector. The ohms have been the only question mark I have seen, with the hi side OK and the low side being well below spec.

Tiny Response from OldLaser
2 questions asked
Replied on July 8, 2008

I assume you have disconnected battery and then ran engine to see if same codes show up ?

Tiny Answered by Docfixit (expert)
18,430 answers provided

Replied on July 9, 2008

Using a Snap On M2500, the codes were 13, 15, 21, and 25.
21 was the temp sensor. The ohms dropped like a hammer, so it has been replaced. Idle changed, but code still apears.
15 is the TPS and/or the Idle Speed Control. The TPS has issues. The ohm range is off, and off the car appears to have drops throughout the movement (saw that tonight). It will go from 3.7 to a 3.2, and back to 3.7, and at one time dropped from 5.2 to 1.9 and back. The drops are repeatable.
13 and 25 are in the air intake mechanism. The ohms check and signal feed appear normal, but the Baro sensor reads 37.9. My Haynes book says 29.9 at sea level and drops with elevation. I tried a second air intake assembly from a junk yard, and the Baro had the same reading.

Tiny Response from OldLaser
2 questions asked