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engine pinging/knocking problem with EA82


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I have a 1991 Loyale EA82 (Canadian car) that has a terrible pinging problem that is driving me crazy! This is what happens.

 

The problem predominately exists when the outside temperature increases. I bought the car in the winter and did not know of the problem until it reached over 15 degrees Celsius (60 Fahrenheit) the following summer. The hotter it gets, the worse it gets. The problem happens often but not consistently. The more I drive the car the better it gets. There will be times that I don’t hear anything for an hour (on the highway) and then I will slow down for an exit and when I accelerate again, the motor sound like it is coming apart. I’ll take my foot off the gas and accelerate once again and no more pinging/knocking.

 

These are the things I have done to try and solve the problem.

 

1. Replaced O2 sensor

2. Replaced radiator (it was starting to overheat)

3. Replaced coolant temperature sensor (improved throttle response but not pinging)

4. Cleaned little "pick-up wires" in Airflow meter (intake track)

5. Timing is at 16 degrees BTDC. If I set it at the recommended 20 it is worse. At 16 degrees the car is noticeably sluggish.

6. Recent tune-up with NGK V-grove plugs, cap and rotor. I also purchased an Accell Super Stock coil but it basically left me on the side of the road the next day (ignition would cut in and out, would stall at idle – old coil is back in and working fine).

 

At this point I'm totally lost! I can unplug the O2 sensor but there is no difference except throttle response goes to hell. I must run high octane fuel 91 or it is considerably worse. My Subaru guru told me that he has seen this time and time again in Loyale’s from 1990 to 1992. There seems to be a design flaw with these years. My questions for the group are:

 

1. Can anyone confirm the 1990-1992 problem that seems to plague EA82’s?

 

2. Can anyone suggest something to me that I may have not thought of?

 

Thanks so much,

Matt

Lethbridge, Alberta

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Guest taprackready

We have a 93 Loyal at work, and it has the same problem. It also has the check engine light on all the time. Took it to a sub dealer and they were not able to fix either problem. We just run premium in it and put black tape over the check engine light. They said the light had to do with some minor function that didn't effect the overall performance of the engine. So much for taking a vehicle to the dealer.

 

Bill

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Hey Matt

 

It could be a sticky vacuum advance mechanism that’s not retarding properly at low vac (high throttle). The advance plate rides on a large diameter ball bearing that can get loaded up with crap. I had a pretty severe interment detonation problem pulling hills with my ’87 GL, I tore the distributor down, cleaned and relubed it (also replaced a bad bushing on one of the mechanical advance weights) and that solved the problem. Worth a try.

 

Gary

 

P.S. Hope you had a great Thanksgiving.

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The EGR valve is on the back side of the intake manifold. It's got a big round vacuum diaphragm on it.

 

Run a bottle of Chevron Techron through it, should help. Also, when you set your timing, you disconnected and plugged the vacuum advance right?

20 degrees seems awful high, mine is supposed to be 12 degrees I beleive (EA82T)

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Thanks for the idea but the newer models do not have a vacuum advance system or weights to control advance.

 

Matt

 

 

Originally posted by All_talk

Hey Matt

 

It could be a sticky vacuum advance mechanism that’s not retarding properly at low vac (high throttle). The advance plate rides on a large diameter ball bearing that can get loaded up with crap. I had a pretty severe interment detonation problem pulling hills with my ’87 GL, I tore the distributor down, cleaned and relubed it (also replaced a bad bushing on one of the mechanical advance weights) and that solved the problem. Worth a try.

 

Gary

 

P.S. Hope you had a great Thanksgiving.

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I know that the vacuum to the EGR is good but I do not know if it pulling EG back or if it is just plugged at the bottom. 20 degrees is spec for the newer models. Their is no vacuum advance on the newer style distributors (crank angle sensor type distributor).

 

Thanks,

Matt

 

Originally posted by Hondasucks

The EGR valve is on the back side of the intake manifold. It's got a big round vacuum diaphragm on it.

 

Run a bottle of Chevron Techron through it, should help. Also, when you set your timing, you disconnected and plugged the vacuum advance right?

20 degrees seems awful high, mine is supposed to be 12 degrees I beleive (EA82T)

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hmm.. Maybe for some reason the computer is not adjusting the timing properly?? Put a timing light on it and rev the engine up, you should be able to see the timing advance itself.

 

I also remember hearing that there are two connectors you are supposed to hook together before setting timing??

 

 

To test the EGR valve: At idle, reach inside the diaphragm housing on the EGR valve and lift the diaphragm up, this will open the EGR valve. If the car starts to stumble (it might die even) then the EGR is working, if it does not stumble, then your passage could be blocked, or the valve stuck open (will idle rough with it stuck open) without EGR, the combustion temperature will rise, which CAN cause pinging (overly hot chamber leads to pre-ignition, fancy word for pinging).

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The EGR valve dilutes the incoming air/fuel mix with inert exhaust gas, effectively taking up space, and therefore lowering combustion temps.

 

How about excessive carbon in the combustion chamber? Anyone recommend a top engine cleaner or the 'water trick'?

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Thanks for the instructions on how to test. I'll try it this weekend.

 

Matt

 

Originally posted by Hondasucks

hmm.. Maybe for some reason the computer is not adjusting the timing properly?? Put a timing light on it and rev the engine up, you should be able to see the timing advance itself.

 

I also remember hearing that there are two connectors you are supposed to hook together before setting timing??

 

 

To test the EGR valve: At idle, reach inside the diaphragm housing on the EGR valve and lift the diaphragm up, this will open the EGR valve. If the car starts to stumble (it might die even) then the EGR is working, if it does not stumble, then your passage could be blocked, or the valve stuck open (will idle rough with it stuck open) without EGR, the combustion temperature will rise, which CAN cause pinging (overly hot chamber leads to pre-ignition, fancy word for pinging).

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I would be very surprised if there is excessive carbon in the cyclinders. I run the old beast pretty hard and the plugs do not have any carbon deposits on them.

 

Explain the water trick!

 

Thanks,

Matt

 

Originally posted by snotrocket

The EGR valve dilutes the incoming air/fuel mix with inert exhaust gas, effectively taking up space, and therefore lowering combustion temps.

 

How about excessive carbon in the combustion chamber? Anyone recommend a top engine cleaner or the 'water trick'?

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  • 1 year later...

Heres what cured mine: (1) new oil pump; (2) run 10w30 in it; (3) new oem pcv valve; (4) do the full Seafoam treatment (suck it in the top, add to gas, add to oil per directions on can), (5)new plugs/wires/rotor/coil. If I had to guess which of the above are most important with respect to ping at high outside temp and under load? I'd go with (1) and (4).

 

Timing: My mechanic swears by 18 rather than the stock 20 for the 1.8 spfi. Works for me.

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What I found worked for me was to first change the spark plugs to one set colder and if they don't foul up on you, all is fine...then I changed the thermostate to 160deg..(my rad is new so the coolant runs very freely thru it)(don't forget to drill the small hole on the thermostate flange)..set the timing to 18deg.at the proper rpm. and us 89 octane gas...if you ever get around to changing your headgaskets, cleaning up the heads will make big difference..

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