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Gen2 Engine Rebuild Needed or not?

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496
461
Exp. Type
HPDE
Exp. Level
Under 3 Years
MD
Well I didn't think I would be creating a post like this so soon. Last event was at Road Atlanta in November. During my last session I got flashing CEL. Car continued to run and fine and never went down on power. CHT was never above 238* and oil temp was never in the red. I came home and the car had P0316 and 0308 codes. I thought maybe it was a false alarm but after clearing the codes they came right back. I am still on the original plugs that I bought the car with (35k miles ago) so I figured to try and replace the plugs. I took the car to my mechanic and he ran a compression test on cylinder 8 which came back 80psi. Fuel trims look good, no loss of pressure, car drives just fine but does have a rough idle. I have no experience with this so in my head I am thinking engine loss and Im done for the year. He said that the ring land broke but I can still save the block. I was planning on changing the oil after I the new plugs were put in but I dont know how beneficial that would be.
My questions are:

What would be your next steps to investigate?

What components should I buy as an upgrade or fix to be back on the road in no time? (Bill at CJPP voice lol)

Also, I still pay student loans and dont have unlimited funds so my bank account does not speak $10k components lol

Thanks for any suggestions!
--Warren
 
So here's my train of thought:
A flashing CEL occurs when a misfire is occurring that is severe enough to cause damage to the catalytic converters. You should never continue to drive with a flashing CEL if there isn't a trophy on the line.
The first thing I'd check would be the ignition system, since you said there was no issue with fuel.
You mentioned you wanted to try new spark plugs, but I couldn't really understand if you had put them in or not by the end. Another thing would be making sure the coil is also working. You can test both by plugging the coil into the spark plug outside the engine and seeing if spark occurs across the tip after removing the fuel pump fuse. You can also test a suspect coil by changing what cylinder it is in and seeing if the misfire code follows it (like swapping cylinders 7 and 8). My Ford book says a working spark plug should measure between 2,000-12,000 ohms at room temperature (77 F) on a multimeter. It also says that the coil should have a resistance of 5,000-6,000 ohms (between the hot ignition wire on the component electrical connector and the coil wire located on the tip of the component in the coil boot) if you want to test them that way. These are from the 2011 Ford Powertrain DTC Diagnosis book, but I believe they're still applicable for a Gen 2 ignition. The ignition coil did get updated after built date 2/23/2016, but to my knowledge that was only a change in the harness connector. The spark plug used across both gens is the same.

As far as compression tests - while you can find numbers online on what 'good' compression is, it depends on how the test was carried out. Usually a better indication is comparing a suspect cylinder's compression to the other cylinders in the engine. When the mechanic said #8 was at 80 psi, did they tell you what the other cylinders were at? I think a better way to check the condition of the rings without taking apart the engine is with a leak-down tester, unless the mechanic did in fact give you compression numbers from the other cylinders that are substantially different than #8.

If you have some more info and do some more testing, let us know the results.
 
496
461
Exp. Type
HPDE
Exp. Level
Under 3 Years
MD
Thanks for the reply. All info is much appreciated. You are right, I shouldn't have continued to drive. I think emotions got the best of me to be honest. Had such great weekend finally finding my groove, no traffic on track, driving 16 hours from MD, and the car still feeling fine, I continued.

So he told me the plugs looked bad and definitely needed changing from visual inspection. Said that there was a little bit of oil on the one of the plugs. Only other cylinder he tested to my knowledge was 7 and and said it was at 170. He did swap the coils around and confirmed it wasn't a coil issue. Found small oil in the hole at 8 also. I took tomorrow off to go to the shop and talk to him in person. Suggested I could replace the one rod, piston, seals and bearings in the meantime but I feel if doing all of that then I might as well do the same for all cylinders.
 
With the higher compression from the other cylinder and the oil in the suspect cylinder he could be right that the rings are pinched. One thing to keep in mind is trying to diagnose the cause, should it just happen again after new parts go in.

If you want to price out what an OEM replacement set up would be, here are some part numbers:

Connecting Rod (includes bolts): CR3Z-6200-B - Ford MSRP is $51.83, can be found online around $36 and from select MD dealers at $47
Piston: FR3Z-6108-A - Ford MSRP is $54, can be found online for $38 and from select MD dealers at $49
Piston Wrist Pin: BR3Z-6135-A - Ford MSRP is $22.73, can be found online for $15 and select MD dealers at $20
Piston Ring Pack: CU7Z-6148-E - Ford MSRP is $33.13, can be found online for $22 and select MD dealers at $28 (currently marked as being on backorder, check with dealer)
Rod Bearing: BR3Z-6211-A - Ford MSRP is $26.83 per pack of 2. Online sells packs of 2 for $19, select MD dealers are around $24
I've found the most economical way to get head gaskets and new head bolts are the Ford Performance packs. In this case, M-6067-M50. It's available on Summit for less than $100.

If you have a local dealer you like working with, it may be worth the small price premium to work with them on getting replacements if you go that route provided they're in line with the MSRP or slightly lower like above. They'll get them to you faster and what isn't factored into the online lower prices is having to pay for shipping and sometimes having dubious stock quantity numbers. A single cylinder basically runs you $168 at good dealership rates for everything above. Fixing that one cylinder and also putting new rod bearings in everywhere is about $336 at the same good dealer rates. Both estimates are before head gaskets/bolts and labor.
 
1,191
2,203
Exp. Type
Time Attack
Exp. Level
5-10 Years
SoCal
Well I didn't think I would be creating a post like this so soon. Last event was at Road Atlanta in November. During my last session I got flashing CEL. Car continued to run and fine and never went down on power. CHT was never above 238* and oil temp was never in the red. I came home and the car had P0316 and 0308 codes. I thought maybe it was a false alarm but after clearing the codes they came right back. I am still on the original plugs that I bought the car with (35k miles ago) so I figured to try and replace the plugs. I took the car to my mechanic and he ran a compression test on cylinder 8 which came back 80psi. Fuel trims look good, no loss of pressure, car drives just fine but does have a rough idle. I have no experience with this so in my head I am thinking engine loss and Im done for the year. He said that the ring land broke but I can still save the block. I was planning on changing the oil after I the new plugs were put in but I dont know how beneficial that would be.
My questions are:

What would be your next steps to investigate?

What components should I buy as an upgrade or fix to be back on the road in no time? (Bill at CJPP voice lol)

Also, I still pay student loans and dont have unlimited funds so my bank account does not speak $10k components lol

Thanks for any suggestions!
--Warren
Did he look in the cylinders with a bore scope? When I broke the ring land in mine, the piece of loose piston dinged the electrode strap on the spark plug, causing it to misfire immediately. Limped it home a short distance from the track for further inspection. The bore scope confirmed the broken ring land.


This is from an inexpensive iPhone bore scope:
IMG_6394.jpeg

This is with the head off:
IMG_6538.jpeg
 
496
461
Exp. Type
HPDE
Exp. Level
Under 3 Years
MD
With the higher compression from the other cylinder and the oil in the suspect cylinder he could be right that the rings are pinched. One thing to keep in mind is trying to diagnose the cause, should it just happen again after new parts go in.

If you want to price out what an OEM replacement set up would be, here are some part numbers:

Connecting Rod (includes bolts): CR3Z-6200-B - Ford MSRP is $51.83, can be found online around $36 and from select MD dealers at $47
Piston: FR3Z-6108-A - Ford MSRP is $54, can be found online for $38 and from select MD dealers at $49
Piston Wrist Pin: BR3Z-6135-A - Ford MSRP is $22.73, can be found online for $15 and select MD dealers at $20
Piston Ring Pack: CU7Z-6148-E - Ford MSRP is $33.13, can be found online for $22 and select MD dealers at $28 (currently marked as being on backorder, check with dealer)
Rod Bearing: BR3Z-6211-A - Ford MSRP is $26.83 per pack of 2. Online sells packs of 2 for $19, select MD dealers are around $24
I've found the most economical way to get head gaskets and new head bolts are the Ford Performance packs. In this case, M-6067-M50. It's available on Summit for less than $100.

If you have a local dealer you like working with, it may be worth the small price premium to work with them on getting replacements if you go that route provided they're in line with the MSRP or slightly lower like above. They'll get them to you faster and what isn't factored into the online lower prices is having to pay for shipping and sometimes having dubious stock quantity numbers. A single cylinder basically runs you $168 at good dealership rates for everything above. Fixing that one cylinder and also putting new rod bearings in everywhere is about $336 at the same good dealer rates. Both estimates are before head gaskets/bolts and labor.
Truly amazing. Thank you so much. This makes me feel a lot better. I’m going to talk to him tomorrow and order the parts. Thank you.
 
496
461
Exp. Type
HPDE
Exp. Level
Under 3 Years
MD
Did he look in the cylinders with a bore scope? When I broke the ring land in mine, the piece of loose piston dinged the electrode strap on the spark plug, causing it to misfire immediately. Limped it home a short distance from the track for further inspection. The bore scope confirmed the broken ring land.


This is from an inexpensive iPhone bore scope:
View attachment 94804

This is with the head off:
View attachment 94805
I asked him a few hours ago and he said not yet but based on the low compression and the drops of oil on the cylinder he is pretty sure there is a leak from the ring land. When this happened did you do a complete overhaul or just fixed that one cylinder?
 
1,191
2,203
Exp. Type
Time Attack
Exp. Level
5-10 Years
SoCal
I asked him a few hours ago and he said not yet but based on the low compression and the drops of oil on the cylinder he is pretty sure there is a leak from the ring land. When this happened did you do a complete overhaul or just fixed that one cylinder?
I went with a built Gen3 shortblock. Hindsight, I should have just went with an OE Gen3 shortblock.
 
496
461
Exp. Type
HPDE
Exp. Level
Under 3 Years
MD
Watched a few videos of YouTube online … to replace one rod/piston assembly, is it essentially the entire engine being torn apart? I know everything from the heads and up come off but does the crank also?
I’m just thinking with the labor cost, I might as well get a Gen 3 block
 
1,063
1,112
Monaca Pa
Watched a few videos of YouTube online … to replace one rod/piston assembly, is it essentially the entire engine being torn apart? I know everything from the heads and up come off but does the crank also?
I’m just thinking with the labor cost, I might as well get a Gen 3 block
That would be the way to go. You would still need cam chains and I would install new oil pump and good oil pump gear.
 
Watched a few videos of YouTube online … to replace one rod/piston assembly, is it essentially the entire engine being torn apart? I know everything from the heads and up come off but does the crank also?
I’m just thinking with the labor cost, I might as well get a Gen 3 block
If you're just replacing the rods & rod bearings, the crankshaft doesn't need to come out provided it has no damage. Getting a new shortblock may be a viable answer, but just wanted to give clarity to both options. It appears that the OEM Gen 3 shortblock is JR3Z-6009-A, MSRP is $3,578.57 with a core charge of $500. Some MD dealers have it for around $3,220 with the same core charge. Just keep in mind if not doing the work yourself that there still is a labor cost associated with putting that in the car and I'd assume also the cost of a new tune.
 
Technically you could pull the one rod and piston combo by just removing the cylinder head covering cylinder 8 and the oil pan. Depending on what went on you could potentially just put a new piston and rings into that cylinder and re-use the rod and even the rod bearings if you're trying to be super frugal. Of course every corner that's cut is another potential failure point too. I'm not suggesting this as the best route, or even the route you should take, but if you're trying to get it fixed as cheap as possible, that's the cheapest way to do it.
 

TMSBOSS

Spending my pension on car parts and track fees.
7,574
5,311
Exp. Type
HPDE
Exp. Level
10-20 Years
Illinois
I went with a built Gen3 shortblock. Hindsight, I should have just went with an OE Gen3 shortblock.
The gen 3 short block is about $3k. I suspect there will be a warranty with the block also. Ask the dealer to confirm.
 
496
461
Exp. Type
HPDE
Exp. Level
Under 3 Years
MD
Thank you all for the suggestions and advice. Went to the shop today and we decided the best route is to go Get 3 block. Didn't find anything new than what was already mentioned yesterday. No leak down test was performed. Im used to seeing people drop 10k+ on new engines so I feared that was what I was up against but I can definitely get parts together and be back by the end of the year. I talked to Shaun at AED and he advised me to go e85 or race fuel going forward so I will do that. I should've done it before to prevent this. I am still thinking about if I should get new heads because he sends them out to a machine shop to make sure everything is fine but at the $500 cost of that, I might as well spend more for brand new. Also may swap my intake manifold and Gt500 valve covers over if possible.

Please let me know if I am missing anything. I plan on staying within NASA TT3 levels so not trying to go crazy with HP
Screen Shot 2024-04-24 at 1.33.56 AM.png

For my 30th birthday this year, I planned on taking a week off work and doing 3 events along the east coast between (VIR, Summit, Watkins, NJMP) but looks like I'll be treating myself to new parts instead. Thank you all again for the advice. I am learning as I go and read.

Also do head gaskets match the block or the heads? I believe the block but just want to make sure.
 
496
461
Exp. Type
HPDE
Exp. Level
Under 3 Years
MD
The gen 3 short block is about $3k. I suspect there will be a warranty with the block also. Ask the dealer to confirm.
Great point. That will at least give me a peace of mind rather than buying one off of someone for a discount.
 
496
461
Exp. Type
HPDE
Exp. Level
Under 3 Years
MD
If you're just replacing the rods & rod bearings, the crankshaft doesn't need to come out provided it has no damage. Getting a new shortblock may be a viable answer, but just wanted to give clarity to both options. It appears that the OEM Gen 3 shortblock is JR3Z-6009-A, MSRP is $3,578.57 with a core charge of $500. Some MD dealers have it for around $3,220 with the same core charge. Just keep in mind if not doing the work yourself that there still is a labor cost associated with putting that in the car and I'd assume also the cost of a new tune.
Thanks man. Gen3 short block is the way.
 
496
461
Exp. Type
HPDE
Exp. Level
Under 3 Years
MD
Shaun did my tunes. Take it to a dyno shop that works with Shaun while the do the pulls.
Thank you. That's what I will do. I heard that he works with Adam at Revolution Automotive so I'll go there since that's 15 min from me
If you use the GT350 IM, you'll need an adapter for the stock TB or the GT350 TB.
yup I updated the list. Thanks
 

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