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what's a crank angle sensor???


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I've been having pinging probs with my 93 Loyale. I did the "water treatment" and changed the Bosch plugs to NGK's. Runs much, much better. yesterday, the check enging light came on. Dealer read the codes and it was: EGR, and Crank Angle Sensor. He said it may be the distrubitor going out. The car still runs better, and no probs, just the light?? What to do?? Also, he mentioned there was a sensor on the AC bracked also, that has to be a certain distance from the ac clutch, but no one there knew much about Loyale's Please help.

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Did you tell the dealer it was a 93 EA82 series car? I'm not sure if the EA82s have a crank angle sensor, I know the EJ series engines do, and those start at 1990. So if you didn't let them know it was an EA82 series engine, they might have read the code for an EJ series engine. What was the code error?

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my haynes manual shows an error code for the crank angle sensor, this is on an ea82 efi engine. I actually got a crank angle sensor code once, but it disappeared and never came back? The crank angle would be on the distributor right?

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Yea, I know we hashed this before, but no one could prove that the EA82 has a crank angle sensor. The one on the EJ series engine is located over the crank and uses a notched wheel attached to the crank at the front to sense the correct crank angle, it is one half of the signal needed to cause the spark plugs to fire, the other is a cam angle sensor mounted on the left cam (on SOHC engine or left intake cam on DOHC engine). Rallyrus, is that diagram from a Subaru FSM?? If so which one, which section and which page?

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Although he is a dealer mechanic, he said that NO ONE takes Loyale's in to be worked on--to old. I'm hopeful that he knew it was an EA 82 engine, it took him forever to find the code reader for the machine. He said that the Loyale has 2 crank angle sensors, the thingy that is mounted on the top of the AC bracket, and hangs over to read a pickup on the clutch, and the one on the distributor, where it plugs into another connection. He said that the disty may be bad, which would lead to the pinging. Also, I noticed some white buildup on my valves, and on the Bosch plug (replaced with NGK---BIG DIFFERENCE), any ideas?? The car is still driving nicely, and the light goes off, but comes back on after 20-30 minutes.

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The thing on the AC has nothing to do with the ignition.. it reads how fast the AC pully is spinning and compares it to the RPMs of the motor.. if theres too big of a difference, it won't turn the AC on.

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my diagram comes from ALLDATA but they usually just scan the factory one and slap it up there. not the most user frendly method.

 

I know it is not what we expect to see as far as a crank angle sensor. in fact I doubt that it has anything to do with this problem. The dealer guy will be rather lost tring to work on your loyal any how. I would either fix it your self or get it to a good independant shop.

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Code reader, that's a good one, the code is a series of flashes of a light diode on the ECU, right under the steering wheel. If you ever go back to that dealer, have that mechcanic show you the code reader he used. Please take along a digital camera because I'd like to see it also.

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Here's part of what a 1990 Loyale FSM says about it: "This distributor is equipped with a photoelectric crank-angle sensor which transmits a crank-angle signal and a cylinder-identification signal to the fuel injection control unit. A signal processing unit, which is built into the distributor housing, cnsists of LED and a photodiode....When the ignition switch is turned "ON", the LED emits light to the photodiode. The rotor plate turns as the engine starts....The "on-off" light signals are transmitted to the fuel injection control unit which determines optimum ignition timing and sends the appropriate signal to the coil....This type of distributor is not equipped with a centrifugal advance angel and a vacuum advance angle device."

 

I don't think you can do much with respect to "maintenance" other than install a new cap and rotor.

 

With respect to the EGR, search the posts for "EGR Solenoid". The consensus seems to be to replace the solenoid (not the EGR valve) with a junkyard version.

 

If you don't feel like doing anything for the moment, a piece of black electrical tape can be customized to perfectly cover your CEL.

 

One more thing: Have you considered a new oil pump? Lot's of "pinging" (lash adjuster noise) is basically a result of low oil pressure.

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The dealer used a palm pilot sized code reader that accepts large cartridges (like the old Atari games--that big) and plugged it into a white plastic-of course- port located adjacent to the wiper motor, and the green test poles in the engine bay. His intitial thought was that the disty was bad. I don't believe in coincidences, and as I've NEVER had the CE light come on until I put different plugs (the correct ones) in, it has to be related somehow. I'll recheck the timing, and I did add some Techron after the light came on, because I saw some white deposits on the valves and the old Bosch plug when I changed them. So I think I have a lean issue, as the engine has never run hot at all. Anyone know how to adjust the leanness on a Throttle body Hitachi?

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The dealer used a palm pilot sized code reader that accepts large cartridges (like the old Atari games--that big) and plugged it into a white plastic-of course- port located adjacent to the wiper motor, and the green test poles in the engine bay. His intitial thought was that the disty was bad. I don't believe in coincidences, and as I've NEVER had the CE light come on until I put different plugs (the correct ones) in, it has to be related somehow. I'll recheck the timing, and I did add some Techron after the light came on, because I saw some white deposits on the valves and the old Bosch plug when I changed them. So I think I have a lean issue, as the engine has never run hot at all. Anyone know how to adjust the leanness on a Throttle body Hitachi?

That SPFI throttle body isnt really adjustable. It's all ran by the computer which relys on its sensors and program to run the engine properly. I would suspect a faulty component leading to your lean running condition before adjusting any air and fuel ratio by hand.

 

If the EGR selinoid was stuck OPEN then it would be constatnly sending air into your intake manifold. This is unmeterd air since it is after the MAF and TPS so the computer isnt compensating with more fuel. Just a thought since you have an EGR code and lean conditions.

 

I'm with Calebz tho; clear the codes and see what comes back. Find the problem before you start adjusting things to compensate for the symtoms :)

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Methinks that's excellent, sound advice, before I muck up anything worse and set off more codes than NASA, a) I'll finish my coffee, B) pet the dogs, c) put their collars on, d) clear the codes, e) pray, f) and go for a drive with the dogs to see if'n any come up. Luckily, there's a junkyard close by with a healthy selection of GL's, DL's and Loyale's, and the owner owes my many favors, so I can get a replacement EGR solonoid if that's the problem. Thanks everyone :D

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You've got to love those tech manual writers and engineers. "This distributor is equipped with a photoelectric crank-angle sensor which transmits a crank-angle signal and a cylinder-identification signal to the fuel injection control unit." I guess that you could calculate the crank angle at the distributor, but with all the slop that can occur between the crank and the distributor, I wouldn't say it was reliable. I guess that they wised up with the EJ series engines since that crank sensor is sensing from the crankshaft directly.

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If the EGR selinoid was stuck OPEN then it would be constatnly sending air into your intake manifold. This is unmeterd air since it is after the MAF and TPS so the computer isnt compensating with more fuel. Just a thought since you have an EGR code and lean conditions.

not really. egr solinoid just allows vacume to be applied to the diaphram on the EGR valve from the manifold. if it were stuck open the EGR would be applied all the time. this allows exhaust gas to dump back into the intake. this would not evin idle most likely.

 

Here's part of what a 1990 Loyale FSM says about it: "This distributor is equipped with a photoelectric crank-angle sensor which transmits a crank-angle signal and a cylinder-identification signal to the fuel injection control unit. A signal processing unit, which is built into the distributor housing, cnsists of LED and a photodiode....When the ignition switch is turned "ON", the LED emits light to the photodiode. The rotor plate turns as the engine starts....The "on-off" light signals are transmitted to the fuel injection control unit which determines optimum ignition timing and sends the appropriate signal to the coil....This type of distributor is not equipped with a centrifugal advance angel and a vacuum advance angle device."

 

see corky Im not just makin stuff up. I have seen it refered to as such on other cars of the same era as well. you are correct it is not a fitting description but they called it that any way.

 

this is why we now have standardized terms/diagnostic connectors ect. and as a technician I love it. I dont have to deal with fords (or any other manufactures) stupid names for simple parts and special tricks to get comunication out of a PCM.

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i dont know why they call it that, but they do.. its the same on my nissan and isuzu also...

and at least our crank pulleys dont get loose and break the keyway out of the front of the crank like the ej22... :(

 

another thing, theres lots of itty bitty holes in a round metal disc, if something falls in there and "blocks" the light from going through one, the ecu will get confused.. you can clean them.. but if its running good, clear codes and see if it comes back.. you may have knocked some dust loose in there if you changed the ditzy cap

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The crank angle sensor actually has 2 outputs. One sends 360 pulses per disty rev to the ecu. The other I believe sends 4 p per rev. The sig level is 0 volts low and +5 volts high. If you know any electronic geek have them back probe the connector and observe the pulses on an oscilloscope. (very fast voltmeter sort of.) Should show missing or erratic pulses if it at fault. Cold beer says it is the wiring and not the sensor.

 

rick

w mi

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not really. egr solinoid just allows vacume to be applied to the diaphram on the EGR valve from the manifold. if it were stuck open the EGR would be applied all the time. this allows exhaust gas to dump back into the intake. this would not evin idle most likely.

Exactly; if the EGR is stuck open thats extra 'air' coming in, unmeterd and uncompinsated for, which could cuase it to run lean.

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