#8 misfire still present after rebuilding injectors

milner351

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I purchased my "new" truck - a few months ago in Lakeland Florida, drove it home to detroit area knowing I was most likely going to be doing an injector rebuild by the way it ran.... rough and smokey.

2001 cc lwb srw 191k, lariat, auto 4x4, all stock for now

After I got into the injectors with the Rosewood DIY kit and found they needed some machining - I sent them all back to Jim Rose for rebuilding (he credited the rebuild kit price - great guy to deal with)

I replaced all 8 sleeves #7 was wheeping coolant)
glow plugs
rebuilt the turbo
gutted the EBPV
and replaced the up pipe donuts while I was at it.

After putting it all back together again - I still have a miss, and a cylinder contribution test shows #8 failure
(before all this work 1,3,8 would fail)
there is a noticeable miss at idle cold and warmed up,
and along with the miss - white smoke out the tail pipe.

On a whim last night I decided to swap out the CPS with my spare
CPS - newer gray and older black CPS - NO CHANGE for me, I've read that others have had good luck swapping to the new dark blue CPS... maybe worth a try, apparently they can be had for $19 online.

I put an ohm meter on the valve cover pins and all injectors on the driver side showed the same resistance - so I don't believe I have an UVCH problem - though I may pull it apart to be absolutely sure.... The UVCH appeard to be replaced before I got the truck - the wires to the GP were still bright white.

The oil pressure sensor in the front of the driver's cyl head also appears new.

I'm open to any and all suggestions - I'm trying to come up with some ideas before pulling it apart and swapping injectors to see if the problem follows the injector or stays with #8.

I dread the thought of pulling the harness apart searching for chafed wires between the valve cover and the IDM on the driver inner fender - but that maybe in my future as well....

What say you?
 

Mike

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Did you have a problem with #8 prior to the rebuild?

Youre on the right track, I would swap holes with the injectors and see if the problem remains in hole 8 or follows the injector.
 

milner351

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I ran the cylinder contribution test a few times before tearing into it - I got errors on 1,3,8 pretty consistantly - #8 every time.

Now running contribution test I only get #8.

There's a pretty good flow out of the CCV on the driver's valve cover - so that has me a bit worried that I might have bought a truck with a mechanical engine problem...which would be a major bummer...
 

OLDBULL8

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Now running contribution test I only get #8.
That's common with #8 on contribution test. It fires right after #6. I would look elsewhere if you have a problem.

White smoke is unburnt fuel. Maybe a compression test maybe in order.
 

Brimmstone

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I know you're not going to like the idea but I would highly recommend doing a compression test on #8. I've had several engines down here show excessively low compression on #8 when chasing a misfire or cylinder 8 contribution fault
 

milner351

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compression is low - it's not an injector or electrical issue

:puke:Compression test shows 140 on #8, 340 on 2,4,6.

Wet compression test shows the same 140.

Compressed air down the glow plug hole didn't help me find where the leak is - I couldn't tell if air was going out intake, exhaust, or crank case.... unfortnately.

I had to put it back together again and drive it - don't have a spare car right now.

I left the #8 injector unplugged - there is NO smoke out the tail pipe now - so the smoke I was seeing was unburned fuel from #8.

Will leaving an injector unplugged do any harm to the IDM?

I've got a quote from a trusted local shop to R&R the head for $560.
I've ordered the gaskets, bolts, and 1in, 1ex valve from rockauto.

The problem is - if I pull the head - or pay my friend to do it - and we find a piston issue - I'm up a creek.

I've found rebuilt heads for $400 ish and rebuilt long blocks for $3000ish on ebay...
the problem is with a 5 month old and a full schedule, I'm not in a good position to be tearing into a major project now, and I need the truck for several tasks in the next month or so.
 

Brimmstone

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Sorry to hear that man. The Stroke is notorious in my area for dropping number 8 due to bad rings. I have one at a friends shop right now that I'll be compression testing Sunday night before I change all the injectors, glowplugs, wiring harnesses, and valve cover gaskets on monday. He had some other shop tell him it needed all that. Good luck man.
 

NJKen

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I hate to be the black cloud on your day here but you are probably going to waste a lot of time and money if you dont pull that engine and tear it down. I know thats hard to do if you dont have the time, money, and another set of wheels to get you around but its the best most economic way to know its fixed. Best of Luck
Ken
 

milner351

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That's a good point about the pushrod - come to think of it - a pushrod on #8 did seem closer to the oil spout on the injector than the others.

The truck is at my friends shop now, I've purchased the gaskets, bolts, and an intake and exhaust valve. He will be tearing into it this afternoon. I'll keep you posted.
 
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milner351

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Well the news isn't good. Sorry I don't have any pictures yet.

Something
(I'm guessing pieces of the compressor wheel thanks to a faulty airbox lid)
got into the cylinder - there are half dozen marks in the top of the piston, and some on the combustion chamber of the head - but that's not really the problem.

Something got between the cylinder and piston and either broke the ring or spread the ring and the excess pressure bored the cylinder oversize a bit - it's like the rings were pressed out harder against the bore than the others.

So - it's time for me to make a decision based on what I can find.

1. good used short block (or long block) less $$ but some risk

2. re-manufactured short block (or long block) more $$ but a warranty - but I doubt that warranty will cover labor - so is it really worth i?

3. re-build what I have -
can you over bore these blocks?
can they be sleeved?
 

OLDBULL8

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http://www.promarengine.com/
Call there to see if they have a short block, and what the cost is. A long block is $5000. See my sig, I was satisfied with an engine from there. Read there warranty, you have to also have a way to unload/load the engine, unless you pickup/deliver at the UPS terminal.

3. re-build what I have -
can you over bore these blocks?
can they be sleeved?

Might be less cost to rebuild yours. They can be sleeved. I think they can be bored up to 0.030 oversize. Maybe just honing would be OK, if the bore is not scored. Only measurement of it will tell you that. Never the less, it's going to take a complete tear down. With ~340 compression, it would be wise to hone all cylinders and a new set of rings.

Only a good trusted diesel mechanic can make that decision.

Good luck, whatever way you go.
 

milner351

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Thanks for the tip - for sure it has to come out - and I will either get a reman'd long block - or rebuild mine. I'm leaning more toward having superior diesel here in detroit rebuild it - they are a family business started in '78 with a good reputation and what sounds like a high quality machine shop with good equipment like Serti, Sunnen, etc.

http://www.superiorturbo.com/

My price on a Ford overhaul kit including oil cooler, head bolts, gaskets, seals, pistons (mahle) rings, injector sleeves (don't need those I just replaced them!) glow plugs (already have new ones of those too) pretty much everything but sensors lines and the hpop - $1250. They are available in .010, .020, .030, .040 over bore. From how #8 looks - I'm thinking I might get away with .010 - which might be able to be done with a hone, not a bore - but that's up to them.
 

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