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Timing Issues On 98 2.0L


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#1
RedDesertCat

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Ok first off this is a continuation from a previous thread I had listed here, but Im writing a new one because my problems have changed to the timing now.
http://www.mazda626....lp-please-read/


Ok so basically I got the MAP sensor issue fixed but my car still wont idle and ran terrible at low RPM, among be sluggish. I was told that the timing could be off so I just got throught with working on the car. I had taken this car to a mechanic to set the timing and cams because I for the life of me could not figure it out even though I did it just like repair manuals state. I got the car back from the mechanic a few months ago and was told that the car runs but its giving a MAP sensor code and only needs a map sensor to run great as it idles bad and sounds like it misses. Either way I took the car and finally got around to fixing the MAP sensor issue as you can see in the link above.

Ok back on track, so I just checked the cam timing and it was wayyyyyy off. I am blown away that it even ran quite frankly. No matter how many times I turned the car over I could not get any of the timing marks to line up, so there is no rhyme or reason to how these cams were timed. Im lost at what he was thinking but he managed to get it running which is one less thing that I could do. I downloaded two Mazda 626 repair manuals, as well as have a Chiltons and did a thorough search on this site so I had valid info on how to time these cams properly. I have added a few pics below of the reference material I used and 1 picture of my marks lined up. I lined up the I on the intake side and the E on the exhaust side so that they were directly across from each other (See pic), And I set the cam gears to where the dowels were straight up as stated in the repair manuals. With the timing marks lined up on the crank, #1 piston was on TDC. I put the valve cover back on and car wouldn't start, wouldn't even attempt to start, it just turned over like it wasn't firing.

I pulled the valve cover to inspect and double check my work and the timing marks were still lined up. I spun the crank with a ratchet twice to double check that marks and everything lined up great. The last thing that I tried was turning the crank 180 degrees and re installing the cams and gears as stated previously. After putting everything back together I attempted to start the car and it wouldn't start, same thing, it just turned over without even attempting to fire.

Im confused now how the car ran (half crappy of course) with the cams installed wrong.....but it won't run at all with them installed as they need to be. Can anyone shed some light on this?? Did I miss something or do something wrong??

Please help as this car is wearing me down big time!

Jordan.

Attached Thumbnails

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  • dowel pin.jpg


#2
RedDesertCat

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Could it be possible that I need to somehow reset the computer so that it adjusts to the new timing settings when i attempt to start it?

Wouldn't this car start up or attempt to start even if it was a tooth off? I swear Im spot on with the timing, but it acts at though I have the coil unplugged as it just turns over without firing at all. But everything is hooked up....

#3
Zoom Zoom 626

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The crank position sensor will cause long cranks but should eventually fire so I doubt that's an issue but id start with making sure everything with the distributor(coil) is right after you've adjusted the tdc and timing marks...and yea id reset the cpu just to try it..

#4
RedDesertCat

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Well the car has a brand new crank sensor as well as ignition coil, plugs, and plug wires. Its distributorless as well as Im sure you know already.

Resetting the CPU is done by removing the Negative battery cable and stepping on the brake pedal correct?

I did remove both battery cables and touch them together for a minute or so, but that did nothing....

Thanks, still looking for answer or direction if anyone can guide me....Im lost as can be at the moment.:( :(

#5
djdevon3

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I don't think touching the positive and negative battery terminals is going to do anything. My guess is the trigger action for the ECU reset is the brake pedal being depressed. Remove the negative lead and hold the brake pedal for 15 seconds. I've heard different estimates of time and I'm not positive about how long it's supposed to be depressed so I'd look that up to be sure. If someone doesn't come along to confirm I'll look it up in the factory manual. I'm too tired right now, rough day.

#6
Tranquility

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I don't think touching the positive and negative battery terminals is going to do anything. My guess is the trigger action for the ECU reset is the brake pedal being depressed. Remove the negative lead and hold the brake pedal for 15 seconds. I've heard different estimates of time and I'm not positive about how long it's supposed to be depressed so I'd look that up to be sure. If someone doesn't come along to confirm I'll look it up in the factory manual. I'm too tired right now, rough day.


The purpose of stepping on the brake pedal is to drain the capacitors in the ECU. Touching the terminals together might drain them if diodes don't block the flow of electricity. I have reset the ECU by turning on the parking lights and removing the negative terminal. Damn, that reminds me, I have to reprogram the radio stations.

As for your current timing issue, it looks like you have the timing belt on right. Since you say the engine cranks, but doesn't fire, check the wiring to the crankshaft sensor and determine if you have spark at the plugs.

Other thoughts about your timing. Use a compression guage to check compression in the cylinders. Major improper timing will have low readings across all cylinders. I am not sure if the camshafts are interchangable, but if not, could it be that your mechanic took the timing gears off the crankshafts and mixed them up? i.e. intake gear on exhaust cam. Others might know the answer to this question, but it would explain your finding the timing marks out of whack.

How far off were the timing marks before you made them right?

Hang in there, you are making progress.

#7
Tranquility

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I pulled the valve cover to inspect and double check my work and the timing marks were still lined up. I spun the crank with a ratchet twice to double check that marks and everything lined up great. The last thing that I tried was turning the crank 180 degrees and re installing the cams and gears as stated previously. After putting everything back together I attempted to start the car and it wouldn't start, same thing, it just turned over without even attempting to fire.


If you truly mean 180 degrees and not 360 degrees, then the #1 piston would be at the bottom of it's stroke during ignition. There would be no compression and no chance of starting. Your pictures are correct if the gears are on their respective camshafts.

Some help here....Are the camshafts interchangeable?

#8
RedDesertCat

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I don't think touching the positive and negative battery terminals is going to do anything. My guess is the trigger action for the ECU reset is the brake pedal being depressed. Remove the negative lead and hold the brake pedal for 15 seconds. I've heard different estimates of time and I'm not positive about how long it's supposed to be depressed so I'd look that up to be sure. If someone doesn't come along to confirm I'll look it up in the factory manual. I'm too tired right now, rough day.


The purpose of stepping on the brake pedal is to drain the capacitors in the ECU. Touching the terminals together might drain them if diodes don't block the flow of electricity. I have reset the ECU by turning on the parking lights and removing the negative terminal. Damn, that reminds me, I have to reprogram the radio stations.

As for your current timing issue, it looks like you have the timing belt on right. Since you say the engine cranks, but doesn't fire, check the wiring to the crankshaft sensor and determine if you have spark at the plugs.

Other thoughts about your timing. Use a compression guage to check compression in the cylinders. Major improper timing will have low readings across all cylinders. I am not sure if the camshafts are interchangable, but if not, could it be that your mechanic took the timing gears off the crankshafts and mixed them up? i.e. intake gear on exhaust cam. Others might know the answer to this question, but it would explain your finding the timing marks out of whack.

How far off were the timing marks before you made them right?

Hang in there, you are making progress.



Oops, I did mean 360 degrees not 180. I reset the ECU by disconnecting the negative cable and stepping on the brake pedal but that didn't change anything. The reason why nothing changed is because I did a compression test afterwards and comp. in all cylinders is way low.

#1 = 75lbs
#2 = 70lbs
#3 = 75lbs
#4 = 65lbs

Im starting to think that you guys are right about the cams being swapped. They could very well be in the wrong places and it all makes perfect sense to me. As far as I can tell the cam gears are identical castings and are interchangeable but doubt that the cams are. I do know that the lifters on these cars are specifically ground for each valve, and CANNOT be swapped to a different lifter bore. So if the cams are swapped then it could be holding the valves open and giving me low compression reading as well as making the car not want to start. This is the reason my car has a remanufactured head on it, because my brother accidentally tipped over the factory head and 10 of the lifters fell out so he just put them back in the bores without knowing exactly where they went. So I just bought a new head as it was cheaper than getting mine fixed. Sorry for the long explanation, been chasing my tail with this car for 6 months now....

Im thinking of swapping the cams (intake cam to exhaust side and vice versa) and seeing if that fixes things. I know that the timing is right, I also know that the car has a brand new head and head gasket so there should be no other reason for low compression than something to do with the cams.

What is a normal compression reading for these cars....120-160lbs?

Ill get back with you sometime tomorrow on what I find after doing the swap, its 112 degrees outside right now so Im going to wait til tonight to work on the car.
thanks
Jordan.

#9
RedDesertCat

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Can someone do a big favor for me? Set your cams at TDC, I & E gears facing each other, dowels straight up just as I do in the picture above.....but take a picture of the cams positions? If I saw a picture of how they are supposed to be installed, then it should be easy to verify if my cams are way different than yours. The lobes on the first cylinders would be in different positions.

It was just a thought as I know no one probable wants to pull the valve cover off of there car. But that would be an easy way to tell if my cams are in the wrong spots.

#10
Tranquility

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I thought about this some more last night. I know the 98 is slightly different, but the exhaust camshaft on the 97 has the distributor drive gear ground into it. This would differentiate it on the 97 models. Is it the same on the 98? Don't know.

In the "How To" section, I found this picture:
http://i11.photobuck...3/VCremoved.jpg
I can't say where the timing marks are, but it might give you something to reference.

At top dead center TDC, both cams should be somewhere on the lowest part of the camshaft lobe. You might be able to turn the crankshaft over 180 degrees at a time to confirm this on each cylinder. This would confirm that the camshafts and gears are installed correctly. Final valve timing is dependant on the timing belt being installed correctly, but you already knew that. :rolleyes:

Also, your compression readings are low. If memory serves me correct, 121 psi is the minimum.

#11
RedDesertCat

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I thought about this some more last night. I know the 98 is slightly different, but the exhaust camshaft on the 97 has the distributor drive gear ground into it. This would differentiate it on the 97 models. Is it the same on the 98? Don't know.

In the "How To" section, I found this picture:
http://i11.photobuck...3/VCremoved.jpg
I can't say where the timing marks are, but it might give you something to reference.

At top dead center TDC, both cams should be somewhere on the lowest part of the camshaft lobe. You might be able to turn the crankshaft over 180 degrees at a time to confirm this on each cylinder. This would confirm that the camshafts and gears are installed correctly. Final valve timing is dependant on the timing belt being installed correctly, but you already knew that. :rolleyes:

Also, your compression readings are low. If memory serves me correct, 121 psi is the minimum.


Well guys, I did it, I got the car running and it runs great......so far (knock on wood).

End result was the cams were in the wrong places, by swapping the cams it put the lobes in completely different positions and the compression jumped up to 165lbs in all 4 cylinders. The car started right up, and besides idling a little to high it runs great. I adjusted the idle just need to dial it in with the A/C in the next few days. Drove the car around the block and has all the power back and runs like a normal car should. THANK GOD ITS FINALLY DONE!!!! After only 2 days of buying this thing it blew a head gasket and I have been struggling to get it running ever since, that was 6 months and over $2500 ago and that doesn't include what I paid for the car. It feels great to finally hear it start up and run like it should. Hopefully I can get some good use out of this car and start to feel like Im getting something out of my investment.

I plan on doing a write up on how to properly install the cams, set the cam timing, and get it running. This was a major pain in my experience because with all the write up there were many unanswered questions that I had. Thanks to everyone that helped me and guided me I appreciate it very much!

Jordan (RedDesertCat)

#12
djdevon3

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Excellent! Can't wait to read your article. Will it have images? Please tell me you took pics.

#13
RedDesertCat

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I took pics :rolleyes:

#14
Tranquility

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Hmmmm, Did you change the water pump????? :lol:

Seriously, Congrates!!!

#15
RedDesertCat

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yes I did thank god! hahahahahaha




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