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I'm wondering if there is a solution to why the base ignition timing is maxed out at only 7 degrees BTDC. I installed a replacement disty (AutoZone part) after the original failed and followed the procedure in the manual to set the base timing. The disty reached as far as it will twist and it only brings the time to only about 7 degrees. I tried 2 distys and same thing. I did not have this problem with the original OEM disty as I remember checking the base timing a while back before it failed. The only other thing that was done to the engine recently and before the original disty failed was the replacement of the timing belt by a local repair shop. Thanks for any advice.

Your timing could be off on the belt. However, if the belt is off then the car will run like crap. Even if only a tooth or two off. That is interesting since I know that I can advance mine well past 10* with the disty if I choose to...

Thanks for your reply Pat. The motor runs OK, but it seems to lack a bit of power. I'll have to get my hands on an OEM disty and see if it makes a difference.

Yes, per shop manual procedure. No offense taken. I read probably most of the posted topics that I could find on base timing and I was surprised that no one has had this problem since disty failure is very common. So I decided to post it. Perhaps we can figure out whether it's the replacement part or something that changed after the timing belt was replaced. I don't think it's "pilot" error, but I suppose anything is possible with rare problems.

I agree, IFR is safer, but not as much fun. Mainly, I do my VFR flying around on road surfaces with my MX-3! LOL


Have a Happy and drive safely everyone!

I gave up giving a crap about my base timing a long time ago. It always ends up readjusting to the same point anyways after enough time running the car for the ECU to relearn. The base disty timing seems to effect idle speed more than anything else.

I guess a few degrees off should not be a big deal, but the base timing should be checked and set once the disty is removed or replaced. Unless the ECU is in service mode it will always try to adjust to programmed timing as equired, which is a good thing. I'm just wondering why my disty is maxed out at 7° and cannot reach the specified 11° while in service mode.

Did you check the cam/crank timing to make sure the belt is lined up properly???
I really cannot see why the disty won't advance any more than it does for you, but i guess that is the question.
There has to be something messing it up. I just cannot come up with a good reason for any part to hold it up...

Pat I did not check the cam/crank timing since the work was done by a service shop. The car runs fine though. Would 1 or 2 notches off have a noticeable adverse effect on engine performance? If not, I guess It may be the problem.

It has in my experience. I'd check it jsut to make sure. Just b/c a shop did it doesn't mean they did it correctly. That is the first reason I got into tuning. A shop did some realyl crappy work on my 1st car, a 82 Chevy S-10 and I decided that was the last time I paid for something I could have learned about and done it myself.
It is not by any means that last time I heard of someone getting a crappy job from a shop either. Hell, Toyota replaced the stereo on my 01' Celica 4 times before they actually found and fixed the problem. It was under warranty was the only reason I didn't do it myself.
PS, the GFs car is the Celica, I bought and paid for, she drives it. I have a MX, what the hell would I want a Celica for???

I know what you mean about some repair shops. Seems to me that the labor rates keep going up while service quality keeps going down. As mentioned, I had a local shop change the timing belt and even though I never changed a timng belt before I regret not doing the work myself. I would also have been beter off if I took it to a Mazda dealer to do the job instead. Anyway, I would not be surprised if they did not install the belt precisely. The car however runs fine. But now that I think of it, I replaced the 1st disty (last year) before the belt was changed. I believe I had the same problem then. Could the crank sensor cause this? I'm not familiar how the timing strip and pulley with marking are mounted. Any chance the timing mark strip or the indicator could have shifted? Thanks Pat.
BTW Celicas are nice cars too! But I also prefer my MX.

No, the timing marks will not move. They are painted on and the ones on the cam sprockets are dented spots. The crank sensor could be going bad, but that should be accompanied by poor running and sputtering. Take it back to the shop and tell them to fix the timing. They did the belt and should have timed it properly the first time. If they cannot figure it out then tell them to give the car back and you'll take it elsewhere. Make sure to tell them that if the way to fix it is not related to the work they did to stop and call you. You don't want to owe for diagnostic time on a new problem.

Are you using a timing light when adjusting the timing?

FlyVFR wrote:Pat I did not check the cam/crank timing since the work was done by a service shop.

That's the kiss of death. You know how many people on Probetalk had a mechanic do thier timing, only to be wrong. First rule of mechanics - none are brain surgeons or rocket scientists. That's why it's better off to do all the work yourself if you can.

Pat, I am using an older induction triggered timing light.

Any chance for the engine's timing marker itself (the strip with the TDC markings) to shift out of position? Is it mounted on the belt cover or cast on the engine block?

I though about having the repair shop look at the timing but I swore that I would not go back there ever again! LOL They displayed strong evidence of shoddy workmanship and incompetence. When I got the car back a few parts (brackets, nuts & bolts) were missing! In addition, it took them almost a week to get the job done while insisting that they were only waiting on back ordered cam oil plugs from Mazda.

lalersfan, I agree 100% and regret not doing the job myself. I would have saved $750.00 on labor charges.

Is there an easier way to check for misaligned timing belt by maybe taking compression readings or by performing a combination of procedures? Or do I have to take the timing covers off and do a visual check?

Thanks!

I just noticed that the shop manual mentions the TDC timing reference mark assy is mounted on the timing belt cover. But I really did not think that it could be the problem anyway.