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- Path: sparky!uunet!zaphod.mps.ohio-state.edu!malgudi.oar.net!uoft02.utoledo.edu!klee2
- From: klee2@uoft02.utoledo.edu
- Newsgroups: rec.autos.tech
- Subject: Toyota Celica ST Ign'n PICKUP COIL
- Message-ID: <1992Aug23.022557.9647@uoft02.utoledo.edu>
- Date: 23 Aug 92 02:25:56 EST
- Organization: University of Toledo, Computer Services
- Lines: 61
-
- To Whom It May Concerned
-
- I spent around 2 weeks in finding out why my Celica ST stalls, either
- at idle or while running. I followed the manufacturer's repair manual
- and suspected that the Ignition Module was the source of the problem.
- The cost of a new IG module costs US$270.00 8-O, ouch!! I called the
- local delar and they told me to check wiring connections. I did, and I
- cleaned up all the connectors with FreonTF Solvant and 111-Trichloro-
- Ethane. The problem is still there.
-
- Today, my car dead again, could'nt start, and as usual, there is a
- Code 6 from the ECU (computer's error code) indicating there is no RPM
- (engine revolution) signal sent to the ECU.
-
- So, I went back to my office and broought a digital multi-tester to the
- parking lot. I disconnected the joint of the PICKUP COIL, and probed
- into it. The Resistance indicated was 1 MEGA Ohms. The specified
- resistance of a IIA pick up coil is 140 to 180 ohms.
- I went back to my office and took another digital meter, It showed open
- circuit (different types of digital meter).
-
- I guess, there I found the problem.
-
- I removed the pickup coil assembly and brought it
- back to my office, and had the resistance checked.
-
- ****** This is what happened ******
- The resistance was infinity from the second digital meter, after a while
- the resistance droped to 165 ohms, which is within the specification.
- Then I suspected the effect of temperture on the resistance of this coil,
- which is beyond my imagination. Maybe there is some other component in
- that little sealed block 1"x3/4"x1/4" whic is temperature sensitive. Anyways,
- I put this little block under a hot water pot and had the temperature of
- the whole block went up. I took the block out and hooked up a meter.
- There I saw something wierd.
- At first, the resistance was high, 500K Ohms, then it dropped.... to
- around 176 Okms with a little bit fluctuating, then stable.
- I put the block back under the water pot, which is hot but less than boil.
- With the Meter connected, I saw the resistance went up (jumped up after
- a stable rising) and it was very unstable. Open Loop was indicaated
- several times, then after 10 seconds, the restance went back to 180 ohms.
- I took the block out and put it in front of the air-conditioner vent.
- At certain temperature, the resistance went up pretty high then came down
- to normal.
- I tried a analog meter. Same phenomena was observed.
-
- I am trying to make sure I found the problem.
- Your opinion and information would be appreciated.
- And hope the abuve discription of the trouble I have would be helpful
- to othes.
-
- Model: Celica ST
- Year: 1986
- Engine Type: 2SE (some CAMRY has the same type of engine)
- Ignition Assembly: IIA (integrated Ignition Assembly) which
- means the ignittion coil (the one with high voltage) is in the
- distributor, and the ignition module is on the fire wall above the brake
- booster in the ehgine compartment. The pickup coil is in the distributor
- as well. There will ba a IIA simble on the original distributor cap.
-
- K Lee
-