The Adventures of Golden Boy, my Rebound E30

[Balleristic31]

If you are still having a hard time passing smog, I have an entire m20 (ETA but doesn't matter) exhaust with a good cat that you could use in Santa Barbara. Kind of a trek but at least it's the same county so you could get it smogged down here.

Just food for thought. Good luck with your motor troubles!

[Jdub]

I don't know much about the m20 motor as I am just now learning as well, BUT I spent a ton of time worrying/changing spark plugs/cap and rotor/new timing belt/cleaning injectors/4 valve adjustments/etc to try to solve that EXACT issue that you're explaining. I have a bumpy idle and a lag with throttle response. After running around like crazy asking every person in every place I can think of for advice, I came to the conclusion that the ticking we're hearing is somewhat normal for the m20 engine. People describe it as a "sewing machine" type sound. Also, people have told me that the bumpy idle is somewhat common as well. If it gives you peace of mind, I drove my car from Chicago all the way to Orlando with the car running exactly like that and it has been running awesome.

Apparently, the ticking can be significantly quieted by Lucas Oil stabilizer (I have a bottle in my trunk that Im putting in tomorrow actually)

And the lag in throttle response is apparently common as well with m20's

HOWEVER, I am so far away from being an expert its ridiculous, I'm just relaying the info I have learned on here and sharing it with you. Hope this helps man, I'll be following you to see how it turns out.

PS. Check the crank position sensor, mine was shredded and I just put a new one in today and it helped a ton with the random misfires.

[CubbyChowder]

I had to adjust the valves on my well worn 2.7L a step tighter than factory spec which quieted things down quite a bit. My temp also never goes to 1/2 mark either. I do have a NOS AFM for later 2.7L motor if you need one.

Sent from my SM-T560NU using Tapatalk

Thanks for your input, I might have to try that out.

If you are still having a hard time passing smog, I have an entire m20 (ETA but doesn't matter) exhaust with a good cat that you could use in Santa Barbara. Kind of a trek but at least it's the same county so you could get it smogged down here.

Just food for thought. Good luck with your motor troubles!

Really appreciate the offer man! If I can get the motor running good and it still doesn't pass then I might just take you up on that.

I don't know much about the m20 motor as I am just now learning as well, BUT I spent a ton of time worrying/changing spark plugs/cap and rotor/new timing belt/cleaning injectors/4 valve adjustments/etc to try to solve that EXACT issue that you're explaining. I have a bumpy idle and a lag with throttle response. After running around like crazy asking every person in every place I can think of for advice, I came to the conclusion that the ticking we're hearing is somewhat normal for the m20 engine. People describe it as a "sewing machine" type sound. Also, people have told me that the bumpy idle is somewhat common as well. If it gives you peace of mind, I drove my car from Chicago all the way to Orlando with the car running exactly like that and it has been running awesome.

Apparently, the ticking can be significantly quieted by Lucas Oil stabilizer (I have a bottle in my trunk that Im putting in tomorrow actually)

And the lag in throttle response is apparently common as well with m20's

HOWEVER, I am so far away from being an expert its ridiculous, I'm just relaying the info I have learned on here and sharing it with you. Hope this helps man, I'll be following you to see how it turns out.

PS. Check the crank position sensor, mine was shredded and I just put a new one in today and it helped a ton with the random misfires.

Thanks for your input man, I know the ticking is just the nature of the m20, however mine is definitely louder than it should be. My buddy brought his 325is over yesterday and his were much more quiet, even though the tick was still very audible. I'm going to experiment with the adjustments and see if I can get it to quiet down a bit.

I cleaned my CPS when I did the timing/cooling service recently but it would probably be a good idea to test it and make sure it's working properly.

I'm a little hesitant about additives, but I'll keep that name in mind

Thanks for the info!

[potatomash]

Engine shaking is probably warn out engine mounts

[Aikmanson]

Engine shaking is probably warn out engine mounts

Not always. The engine I just removed ran very well, idle'd strong, pulled strong, but would occasionally shake at idle (while the idle stayed beautiful mind you). Upon removal I suspected the engine mounts to be shredded. Well I was wrong, they looked sweet. I switched to 85A poly mounts with the new engine but still.

OP, It really sounds like your cam is worn to me. That's the only issue I can pinpoint with my old engine as well. I wish I had a spare cam to send you, I have a spare good condition head for sale for cheap, but I am sure you don't wanna go that far into it.

How does the car run otherwise?

[CubbyChowder]

Engine shaking is probably warn out engine mounts

I actually just installed brand new motor mounts a few weeks ago, so I don't think that is the culprit. Unless the aftermarket brands can cause that, come to think of it I remember that one guy mentioned earlier in my thread that his new mounts caused his motor to shake, so maybe it's worth looking into!

Not always. The engine I just removed ran very well, idle'd strong, pulled strong, but would occasionally shake at idle (while the idle stayed beautiful mind you). Upon removal I suspected the engine mounts to be shredded. Well I was wrong, they looked sweet. I switched to 85A poly mounts with the new engine but still.

OP, It really sounds like your cam is worn to me. That's the only issue I can pinpoint with my old engine as well. I wish I had a spare cam to send you, I have a spare good condition head for sale for cheap, but I am sure you don't wanna go that far into it.

How does the car run otherwise?

Hopefully I can get a chance to inspect the cam this week and see where I'm at. The car seems to run fine otherwise. To be honest I'm not exactly sure how a healthy M20 should feel so I have nothing to compare it to. The idle isn't jumpy, it actually stays pretty consistent and I don't feel any sudden hesitations or power cutoffs during acceleration, it just seems like it should have more oomph when I get on it (I was under the impression that M20's are fairly "torquey"). The valves just seem extra noisey, they are very audible during acceleration, and it seems they are especially loud towards the front of the engine. It just doesn't sound right.

[CubbyChowder]

Well, you guys were right, the cam is toast.

Had a chance to pop the valve cover today to inspect everything and noticed some carnage on the #1 cylinder (closest to the front of the car) area. This is also where most of my valve noise seems to be coming from when the motor is running.

First off, the #1 intake rocker arm looked brand new, while the other 11 rockers looked original and dirty. I think this is where the issue starts, as it seems that when the original rocker arm broke it caused some extra damage, because both #1 intake and exhaust camshaft lobes had chunks missing out of them, like part of the lobe had chipped off (possibly due to the impact of a broken rocker arm hitting it?)

It was hard to get pictures of it, but you can see them circled here:



Along with the missing chunks, the intake lobe looked super worn down when viewed from the top, shown here:



Besides that, there were other areas inside the cylinder head casting near #1 that had small gouges which I assume happened when the arm broke. I just wonder how they replaced that one rocker arm, don't you need to remove the head in order to do that?

Anyways, so now I'm exploring my options here. What I'd really like to do based off the short amount research I've done is spring for a BimmerHeads 885 head with the 274 reground cam, which would run me about $1100 after core charge and everything. That option would have to wait a while since I'd need to save up some money.

Another option would be to find a healthy lower mileage M20 and swap motors altogether, which would definitely be cheaper but significantly more work.

Or I could just rebuild the head myself, however I think I'll end up spending just as much if not more money as a rebuilt BimmerHeads unit.

What do you guys think would be my best route? I simply don't have a lot of extra time or money, which are two big factors working against me. Looking for some advice. Thanks guys

[lambo]

I would say find a nice M20 to swap in there. You have a lift so swapping the motors should be a relatively quick process. So yeah, I'd say find a nice m20, do a few seals and stuff while it's out of the car and then drop the old one out for the new one. I don't know what kinda damage that cam carnage could do to the bottom end. But, it's one of those things where, if I were you, I wouldn't want to have spent >$1k on a nice head only to pull the old one off and have issues down there. If I were you, I'd get another M20, refresh it and swap it for the time being. Then, if you are able to (and you're interested in an M20 build), you could go through your old one, assuming it's not scrap, and procedurally build it at your own pace.

[CubbyChowder]

I would say find a nice M20 to swap in there. You have a lift so swapping the motors should be a relatively quick process. So yeah, I'd say find a nice m20, do a few seals and stuff while it's out of the car and then drop the old one out for the new one. I don't know what kinda damage that cam carnage could do to the bottom end. But, it's one of those things where, if I were you, I wouldn't want to have spent >$1k on a nice head only to pull the old one off and have issues down there. If I were you, I'd get another M20, refresh it and swap it for the time being. Then, if you are able to (and you're interested in an M20 build), you could go through your old one, assuming it's not scrap, and procedurally build it at your own pace.

I am definitely a bit nervous about what potential damage those metal shards could've done to the bottom end, that was the first thing that came to mind when I discovered the chipped lobes.

I think you're right though, with my lift and a few buddies I should be able to pull that off fairly quickly. There actually is a pretty low mileage M20 in the classifieds which is only a few hours north of me, might have to hit that guy up.

Thanks for your input man

[fresh_TD]

The cheapest and quickest solution, would be to find a good used head, drop it in, and continue to drive car. Then save money for a built head if that's the route you choose to go. Swaping an entire engine is completely unnecessary.

[CubbyChowder]

The cheapest and quickest solution, would be to find a good used head, drop it in, and continue to drive car. Then save money for a built head if that's the route you choose to go. Swaping an entire engine is completely unnecessary.

That is true. Wouldn't I still need to get the head tested/decked/valve grind, etc? I think that costs around $400-500 alone in my area. I'm not opposed to the idea at all, just weighing all my options.

[fresh_TD]

That is true. Wouldn't I still need to get the head tested/decked/valve grind, etc? I think that costs around $400-500 alone in my area. I'm not opposed to the idea at all, just weighing all my options.

For example, If you happen to get a known working head from a friend who's doing a swap, no need for all the extra. If you're going to go with a head from a junkyard and have no history on it, then common sense would be to at least get it looked at by a shop, to make sure is good to go.

[ThatOneEuroE30]

The cheapest and quickest solution, would be to find a good used head, drop it in, and continue to drive car. Then save money for a built head if that's the route you choose to go. Swaping an entire engine is completely unnecessary.

He doesn't know if any metal got down into the crank case though. So swapping an engine might be the best thing or at least buying a whole motor then he can pull the head off old and see if it can just have a head done and if it doesn't then he's already got an m20 sitting there ready to drop.

[lambo]

It would be pretty dumb to buy a used head and swap it without having a shop deck it, at the very least. Regardless of if you know the history or not.

[CubbyChowder]

Yeah I'm not sure if I'd be comfortable with throwing a different head on there without having it decked first. I'd just hate myself if I went through all the work only to have to undo it all again. Gonna do whatever I can to ensure I only have to do this once, and yes the mystery shards of metal have me concerned, however I think this motor has been running as is for quite a while now (previous owner daily drove it for 2 years and never mentioned anything about the rocker) so I think he didn't even know about it. But then again, it was a Craigslist deal and I wouldn't be surprised if he purposefully left info out.

I'll definitely be keeping an eye out on a good condition head as well though just in case something solid pops up.