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420A 99 Eclipse GS 420a possible timing off?

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Sephent

Proven Member
61
2
Feb 18, 2016
Medford, Oregon
Hey all. So I picked up a 99 Eclipse GS 420a.

Had some idle issues and would die easily, mostly due to a weak hose going from intake manifold to head, which I fixed.

Previous owner just replaced the timing belt and water pump, and swapped the camshaft position sensor & IAC valve with used ones from a wrecking yard. I have replaced the spark plugs and soon wires, and did an EGR delete (which helped the idle out a lot).

No check engine lights. Usually idles at 800-900 RPM. At a stop it will sometimes suddenly drop rpm to 300-500, almost die, then jump up to 1200 or so to save itself, if it did not die.

Also, seems to hesitate for a second when I start to accelerate from a stop. So I now just expect it to hesitate and am extra careful/slow with releasing the clutch pedal from a stop and feather the gas. Once I start going I don't notice any issues. SOMETIMES I can feel the car slightly hesitate while at a cruising speed (45mph or so) as if I was lightly tapping on the gas pedal.

Only mods I believe is the air intake, DC sports headers, Greddy catback exhaust (muffler portion seems to be falling apart inside, not sure if it's causing issues. Tried to show in video). The car sounds like an old v8. Kind of like how my other car sounded when the timing was off, but not sure if the headers would cause it also. Here's a video.

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I am going to check to see if he messed up the timing, was just hard to see some of the markings, but was curious if you guys think the timing is off, or something else?

I'll check the timing marks today best I can. If the timing is off a tooth or so, is there any easy way to fix it? I don't need to replace the water pump or anything because the last guy did that. I'm guessing I'd still take off the 2 accessory belts and move some stuff out of the way so I can get to the tensioner. Then just loosen the tensioner and adjust the belt, correct? No need to do like a full timing belt change procedure?

Thank you in advance for any help.
 
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Solution
Fixed the timing.

Ended up being a bigger pain than expected. Basically had to do the complete timing belt job and pull the harmonic balancer, which was a biiitch LOL.

And had a partially stripped spark plug threads in the head finally give and shoot my spark plug out, LOL. Helicoiled it for the first time and seems to of held up great :) got it done and replaced the 2 accessory belts while I was at it (they looked pretty worn down).

Sounds amazing now. Nice and smooth. It DID have a little idle surge, but I put the PCV back into the hose going from the intake to the head and it cleared right up, but it IS whistling if that is normal. (when the timing was off, the PCV made it idle worse, so that's why it was off to begin with)...
Sounds like it has cams but I could be wrong. Mine has a rough idle issue so it has the same hesitation under load. You have a cold air intake, does it have a mega squirt or some type of piggy back? From my understanding a CAI needs a tune to properly work.

Edit: I just watched the video, looks more like a short ram intake so never mind that CAI info.

@BLACK'98DSM might be right on the misfire, check the ohms of your spark plug wires make sure to test the coil pack as well. Make sure your plugs are gapped right as well.

Also did he only replace the belt? Or did he actually time the engine properly and replace the belt. If it was done properly you don't need to get it timed again for another 60k miles.
 
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From my understanding a CAI needs a tune to properly work.

A cold air intake is not a harsh enough modification to need a tuning solution. Cams and other internal modifications are what requires tuning. Basically all the bolt-on modifications can be done without a tune.

If it were timing it would be messed up all the time. Not just occasionally. Sounds to me like a misfire.
 
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I'm just not used to the idle sounding like that. All loping... Sparkplugs are gapped to about .044. All he said was that he replaced the timing belt with the water pump. I saw he had 2 tensioners (the circle ones) left over in a box. Assuming the belt he bought came with 2 replacements. I also noticed he had 3 seals still in their bags. The timing and cam seals (round brownish looking things). I have some new wires showing up today. And I just found out that my spare MSD coil pack #8239 I have for my 05 Neon srt4 is the exact same one for the 99 eclipse :D so I'll swap that over and see if it helps
 
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I would start with a compression test. The timing could very well be off, 1 tooth you may not even notice, but it depends on which cam and which direction it's off. I drove around for a year once being off 1 tooth and never noticed it.
 
The timing looks to be a tooth off. I can't see the crank mark to see if it lines up, but at TDC, this is the cam gears. Ugh.

Is there an easy way to just adjust the belt on the gears? Or do I have to do a full timing belt replacement procedure to line everything back up?

I put in a different coil pack and new plug wires and it does run better. Just lopes at idle. Is the timing being a tooth off like this harmful to the engine?

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The timing looks to be a tooth off... I can't see the crank marking to see if it lines up, but at TDC, this is the cam gears. Ugh... Is there an easy way to just adjust the belt on the gears? Or do I have to do a full timing belt replacement procedure to line everything back up?
I put in a different coil pack and new plug wires and it does run better. Just lopes at idle. Is the timing being a tooth off like this harmful to the engine?
Being a single tooth off is not harmful. But If you have the time and skill to fix it then don't just ignore it.
 
Someone said that I could just remove the tensioner, line up the cams, then put the tensioner back on. Would that work? Or would I have to just pull everything like a normal timing belt change?
 
the timing cover was left off... i am looking at write ups for it.. is the tensioner accessible with the motor mount still in place?
Have you even looked?

If the timing cover is off then you should just be able to pull the plastic covers under the bumper/fender and access everything you need to do this.
 
Awesome thank you. I have looked, but been really busy with work and it getting dark early that I haven't had a chance to pull the wheel well plastics.

First time dealing with a hydraulic tensioner too. It's weird LOL. So was just trying to get as prepared as possible.

I'm going to try to fix the timing today. Does the belt go around the crankshaft part that you pull off with the pulley? Hoping to be able to use the tool to pull that so I can physically see the arrow markings instead of just relying on the TDC using a screwdriver in #1 spark plug spot.

I appreciate all the help
 
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Fixed the timing.

Ended up being a bigger pain than expected. Basically had to do the complete timing belt job and pull the harmonic balancer, which was a biiitch LOL.

And had a partially stripped spark plug threads in the head finally give and shoot my spark plug out, LOL. Helicoiled it for the first time and seems to of held up great :) got it done and replaced the 2 accessory belts while I was at it (they looked pretty worn down).

Sounds amazing now. Nice and smooth. It DID have a little idle surge, but I put the PCV back into the hose going from the intake to the head and it cleared right up, but it IS whistling if that is normal. (when the timing was off, the PCV made it idle worse, so that's why it was off to begin with).

I'm soooo happy I finally got it fixed! (The smoke coming out of the exhaust cleared up after I took it for a quick drive. I'm guessing it was from buildup in the engine due to the misfire and timing being off and it was burning it off) Now time for the misc. other stuff with this car (airbag light. Window rattle/not rolling up straight so it doesn't seal completely, and hopefully my worn control arms hold up fine. No bad wheel vibrations or anything yet.

Thanks for everyone's help!
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Solution

Okay so I see he fixed it, I literally have the same problem, same noise, and same situation with previous owner replacing the timing belt and water pump. Only thing is my idle is actually at like 200 rpm’s -500 or something sits above the 0. I am going to try fixing the timing as well and I don’t know how to change the belt so I am going to have to pay someone, I just hope it is that. for now I’m going to get a new pcv valve in

Fixed the timing.

Ended up being a bigger pain than expected. Basically had to do the complete timing belt job and pull the harmonic balancer, which was a biiitch LOL.

Mine turns off at times as well but I see yours idles closer to the 1 mine idles super low it is almost at the 0
 
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Hey. Yeah I ended up fixing it. It WAS the timing off a tooth.

I didn't want to check it because the guy swore he changed it and did it right and then had a shop double check it. And I didn't want it to be the timing belt because it sucks replacing those. But it was indeed the timing.

It is very easy to have it move a tooth when you tighten the tensioner and release all the tension on the belt. So you usually have to get it a tooth or so too far, so then when it moves, it stops where it is supposed to be. Even if it's off just a half a tooth, which is barely anything, it can cause a lot of issues. It sucks.

There are a lot of videos and guides on how to check it if you want to see for yourself. Or if you know a shop you can trust, they can check and determine if it's off or not.

Replacing the pcv valve with an oem mitsubishi one helped as well. The cheap ebay ones fail easily. And just make sure all your hoses are fine and secure. When I bought the car, it had an even worse idle, and would die easily. I noticed that the rubber hose on the top of the engine coming from the top of the head I believe was a super cheap thin rubber hose and the vacuum caused it to collapse on itself and basically pinch the hose, which then caused it to bog down and eventually die.

Let me know if you have anymore questions and I'll try to help the best I can. I don't have the car anymore, but can try to remember all I can.
 
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