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Discussion Starter · #1 ·
Help!!! New plugs, new wires, new distributor cap, new rotor cap, new pick up coil, new ignition module and two new injectors, and another computer. The odd side fires hot but the even side not so much with number 6 not fifing at all. Timing seems right, fires right up, valves are working properly, both injectors working, both seem to have the same spray. Ready to set it on fire and walk away
 

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Firing order on this engine is 1-2-3-4-5-6 around the cap clockwise; I don't see how it would be possible for the control system to "miss" every other spark. The only thing that I can think of that would cause this kind of problem is the distributor cap.

With all the poor-quality parts we get nowadays, I'd trust nothing. Did you have this problem with the old cap? I'd throw the old cap, if you still have it, back on and see what it does.
 

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Discussion Starter · #3 ·
Firing order on this engine is 1-2-3-4-5-6 around the cap clockwise; I don't see how it would be possible for the control system to "miss" every other spark. The only thing that I can think of that would cause this kind of problem is the distributor cap.

With all the poor-quality parts we get nowadays, I'd trust nothing. Did you have this problem with the old cap? I'd throw the old cap, if you still have it, back on and see what it does.
It did it with the old one, that’s why I changed it and the rotor, plugs and wires
 

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Discussion Starter · #4 ·
Also cylinders 2 and 4 are firing but 6 isn’t. I pull the plugs and look at them and they don’t seem to be burning as hot as the odd side. I even replaced #6 plug with one of the old ones from the other side just in case the plug was bad and it made no difference
 

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Have you checked compression on #6? Might have a burnt valve, leaky head gasket, or other issue. Does #6 have spark (put a timing light on the plug wire while it's running)?
 

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Discussion Starter · #6 ·
6 has spark. Seems like the plug keeps fouling. Pulled the distributor again and checked it over real good put it back in and cleaned and regapped the new plug and put it in. Fired right up ran good just a minute and is missing again. I’m letting cool down and pull that plug and check it. I can pull the wire off and you can hear it sparking. I’m going to check all the plugs again and see what they look like
 

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So it would appear that #6 has a pretty bad oiling problem, if it's fouling plugs that quickly. Could be something as simple as valve guide seal(s), or could be badly worn valve guide(s), piston/piston ring problems, scored cylinder. A compression test would tell a lot.

Valve stem seals could be done in place; you'd put #6 at Top Dead Center on its compression stroke, then either use an air holding tool in the spark plug hole, or even simpler, stuff a bunch of thin twine/rope into the cylinder until it's full. That'll prevent the valves from dropping when you pull the rockers & valve springs.

Use a valve spring compressor. Lisle makes a number of different tools that would do the job.

The intake valve has an actual seal fitted to the top of the valve guide. The exhaust valve OE seal is the "umbrella" type, which just rides on the valve stem and keeps extra oil from running down the stem, directly into the valve guide.

You need a positive seal on the intake valve, because of vacuum generated on the intake ('down') stroke. The exhaust side doesn't see a negative pressure, so it's not prone to sucking oil down the guide. It'd have to be worn really badly for that to happen. The most likely one to be bad, therefore, is the intake side.

Note that when rebuilding these engines, it's recommended to machine the top of the exhaust valve guide to accept a full seal, and Viton seals are recommended for best sealing and longevity.

At least the problem is on the driver's side, much less things to pull out of the way to remove the valve cover.

Anyway, take a compression on #6 and cylinders adjacent and see how they compare. Let us know what you find.
 

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Discussion Starter · #8 ·
So it would appear that #6 has a pretty bad oiling problem, if it's fouling plugs that quickly. Could be something as simple as valve guide seal(s), or could be badly worn valve guide(s), piston/piston ring problems, scored cylinder. A compression test would tell a lot.

Valve stem seals could be done in place; you'd put #6 at Top Dead Center on its compression stroke, then either use an air holding tool in the spark plug hole, or even simpler, stuff a bunch of thin twine/rope into the cylinder until it's full. That'll prevent the valves from dropping when you pull the rockers & valve springs.

Use a valve spring compressor. Lisle makes a number of different tools that would do the job.

The intake valve has an actual seal fitted to the top of the valve guide. The exhaust valve OE seal is the "umbrella" type, which just rides on the valve stem and keeps extra oil from running down the stem, directly into the valve guide.

You need a positive seal on the intake valve, because of vacuum generated on the intake ('down') stroke. The exhaust side doesn't see a negative pressure, so it's not prone to sucking oil down the guide. It'd have to be worn really badly for that to happen. The most likely one to be bad, therefore, is the intake side.

Note that when rebuilding these engines, it's recommended to machine the top of the exhaust valve guide to accept a full seal, and Viton seals are recommended for best sealing and longevity.

At least the problem is on the driver's side, much less things to pull out of the way to remove the valve cover.

Anyway, take a compression on #6 and cylinders adjacent and see how they compare. Let us know what you find.
 

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Discussion Starter · #10 ·
Ok, the above pics show what my plugs look like now here are the compression readings
1-140
2-135
3-120
4-130
5-60
6-137
#5 and is firing with 60lbs of compression and #6 is not firing in the cylinder with 137lbs of compression
 

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Not good. #5 has a big problem for sure. The only one I see that's "normal" is #1 with a tan insulator. #3 and #5 are white, probably being washed by unburnt fuel.

The driver's bank is sucking a lot of oil, especially to foul #6 and put that much oil on #2 and #4 with very little running on new plugs.

You can try squirting a tablespoon or so of oil in #5 and re-doing the compression check. If compression goes up a lot, bad rings. If little or no rise, a burnt valve.

About the last thing before scrapping the engine or tearing into it for refresh/rebuilt would be to pull the Passenger's side valve cover, turn over the engine and see if #5 cyl's rocker arms are moving properly. A "dead" hydraulic lifter or flat cam can be the cause of low compression. Check the others cyls for issues as well.
 

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Discussion Starter · #12 ·
Thanks Ed, I was waiting on your reply. I don’t have any oil smoke, it doesn’t smoke at all but I understand what you are saying with the plugs being wet. Number 5 surprises me, I’m going to pull the heads and go from there but that’s my luck. What would be a good replacement engine?
 

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Can't recall if yours is a 2wd or 4wd, is the starter on the driver's side? If so, a 3.1 from a ZuZu pickup will also fit. A 3.1 out of an early GM FWD minivan (Lumina APV, Pontiac TransPort, Olds Silhouette) will plug in. Those 3.1's had the TBI intake, cast-iron heads, starter on the driver's side (if oriented to a RWD application).

If you have a 2wd, I believe those used a Borg-Warner trans and had starter on the Passenger's side. An early-90's Camaro/Firebird would be a plug-in.

If you pull the heads and there isn't much of a ridge on the cylinders, you could just use a glaze-buster balls-hone on the cyls and re-ring it. A valve job should freshen-up the heads just fine. You could get a reground "torquer" cam for a bit more Beans.

Delta Cams in Tacoma is pretty reasonably-priced, you can also get one from Comp Cams but the kit with required special valve springs is a bit $pendy (around $440 shipped). I used a Delta Cams regrind in a "3.2" build back in 2005 and was very pleased with the performance.


Note that you could also use a 3.4 out of a '93-'95 Camaro/Firebird for the ultimate swap. Just depends on how much $$ you want to pour into the project. The 3.4 has the starter mounted on the Pssgr side, so you'd need a Rodney Dickman Fieros drilling jig (under $100) to drill holes for a 4wd, driver's-side-mounted-starter application. BTW you could do the starter relocation to a right-side-mounted 3.1 as well.

Anyway, that's just some general info, guess we'll see what it looks like with the heads off, and go from there!
 

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Discussion Starter · #15 ·
Glasses Automotive tire Wood Motor vehicle Road surface
Automotive tire Motor vehicle Wood Audio equipment Automotive exterior

top picture is 2,4,6 with #2 at the right
Bottom picture is 1,3,5 with #1 at the left. Sorry it’s been so long but with having the covid, our 25 year old son passing away and storm clean up from hurricane ida it has been a long month and a half
 

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No Worries, Mate, that's a lot to go thru. Condolences to you and your family.

Them heads are all over the place! I see a few cylinders actually had nice tan deposits, others very oily. What do the cylinders look like?

Try spraying carb cleaner into each intake port and each exhaust port. If you have a leaky valve, it'll run right out into the combustion chamber. Check also the valve stems thru the port, if the engine is sucking a lot of oil, there should be a lot of carbon deposits on the valve stems.

How's the ridges at the cylinder tops? Any scoring on the cylinder walls or other damage present? You may want to crank the engine over by hand to check each cyl.
 

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Discussion Starter · #17 ·
No Worries, Mate, that's a lot to go thru. Condolences to you and your family.

Them heads are all over the place! I see a few cylinders actually had nice tan deposits, others very oily. What do the cylinders look like?

Try spraying carb cleaner into each intake port and each exhaust port. If you have a leaky valve, it'll run right out into the combustion chamber. Check also the valve stems thru the port, if the engine is sucking a lot of oil, there should be a lot of carbon deposits on the valve stems.

How's the ridges at the cylinder tops? Any scoring on the cylinder walls or other damage present? You may want to crank the engine over by hand to check each cyl.
As far as the cylinders, number 1 you can barely catch a ridge with your fingernail. I’ve seen one that I remember we had to ream the ridges out of the cylinders just to get the pistons out. I have no ridges. The heads acted like the gaskets didn’t seal, you could almost pull them right off with no problem. The intake was harder to get off than the heads. I’ve never seen any oil smoke at all from the engine, not on start up after sitting overnight or any other time. I did have a lot of carbon buildup on the even side, I’m going to pull the egr valve off and clean all that up and out. I’m lost
 

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Maybe the heads weren't properly torqued. The bolts should have been pretty tight. The head bolts on these are Torque-To-Yield and have a specific tightening procedure. And new bolts should be used every time the heads are apart.
If the cylinders look good and you find leaky valves, maybe that's the issue. Especially cyl #5 with the very low compression. If you don't find the valves leaking on #5, it could be a piston ring issue.

BTW how do the cam lobes look? I'd definitely be looking at #5 since a cyl with flat cam can be a cause of low compression as well.

Maybe you'll get lucky and all it needs is a valve job and head resurface.
 

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Discussion Starter · #20 ·
I’m going to look at the cam and see but it will be day after tomorrow. I’m disabled and when I do stuff like this I have to take the next off because I hurt so bad. After I get the heads worked I’m leaving the intake off and checking the lifters on #5 before I put it all back together. I’m just going to put those two pushrods in and turn it over by hand to make sure one isn’t bad. Thanks Ed for the condolences and for all your help. I will post my findings
compression test
i did a compression test before I pulled the heads and posted the numbers earlier
 
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