Why My Engine Blew....

beefcake

Authorized Vendor
Authorized Vendor
Joined
May 16, 2001
Messages
8,986
Location
Cincinnati, OH
I know all have had lost of speculation, too much power, bad gas, bad tune, etc..

From everything we've come to investigate about the engine. Our best guest the cause of the problem was the Caspers Electronics o2 extension harness.

After putting the new engine back in the car, we had issues right out of the gate with random o2 codes on bank 2. SCT Data logger was randomly not picking up a/f out of bank 2. 95% of the time, getting no reading.

I bought 2 new o2's thinking the old ones possibly got oiled from when the motor let go.

Put them in, and immediately had the same codes and no a/f. One time it would be o2 sensor code, then heater circuit code. etc.. All random codes related to the o2 sensor on bank 2.

We pulled the new o2's back out of both sides and got to looking at them closely. What we found was a little interesting. The passenger side, which had no harness extension, when you look at the holes the o2 plugs into. There is gold (connector) right at the tips of the holes.

On the Caspers harness. The gold (connector) is recessed inside the hole nearly half an inch. On top of that, the clip was busted on the connector. My guy at the shop said, hmmm, makes sense now. I asked what he was referring to. Originally the engine builder sent me a pic of one piston. I thought only one was gone. Turns out that all 4 bank 2 pistons were ate up. 5,6,7, and 8. The guys at my shop said that there was my problem.

More than likely, there was very little connection in the harness. When the clip broke, not enough connection to hold. We played around with the stock harness for a bit and was able to move it around and plug the factory harness in to the o2 without the connector.

Jump into the car, fire it up, and voila! No o2 codes and a/f was reading fine.

At Bradenton this past week, I was talking with my tuner and started talking to him about the harness. As soon as I mentioned header harness, he got a faint grin, not laughing, but like knowing what I was going to say.

He told me the American Racing shop car had tuning issues for a few weeks. He was remote tuning the car, and told them there was no issues with the car, it had to be somewhere else. They discovered the same thing, the harness was the issue with the car.

There was also another car that showed up at the NMRA race that was having similar code issues. Turns out he has headers with the same harness. (everyone uses these harness').

Also talked to Justin from VMP, told him my findings, he told me that he had recently went to order some of the harness' from Caspers and they told them they were "redesigning" the harness because of the clips breaking.

I talked to them myself today, moreso about the connector vs the clip. He said they use oem connectors. I assured him the connectors look nothing like oem. Then he told me they are "bosch" oem connectors.

Again, best guess is the clip had broken at some point and lost connection, more than likely under wot. John Lund explained to me that these cars when they don't pick up a reading, default to a 14 to 1 a/f. More than enough to detonate a s/c'd Coyote at WOT.

Bank 1 was completely untouched in the engine as well.

So, there ya have it.
 

kleistang

Member
Established Member
Joined
May 12, 2009
Messages
405
Location
Miami
damn that sucks.

thats definitely the most expensive o2 extensions you would ever buy.
 

Kevinz00GT

Member
Established Member
Joined
Dec 19, 2004
Messages
95
Location
Biloxi, MS
I have been talking back and forth with Jon Lund as well on the exact same issue. Loaded the tune on my car after installing a full stainless works system and it has run real sluggish right out of the gate unless you are at w.o.t. I have had a substantial loss in mpg as well. I spoke with stainless works a couple of days ago and they are aware of the issue but unfortunately Casper is the only one manufacturing o2 extensions at the moment and they are "waiting to hear back from them.". Hopefully someone else will step up and make these.....racetronix does some nice work but I have only used their stuff in ls powered cars and I really don't know if they cater to the mustang crowd
 

GetBlown2k3

Active Member
Established Member
Joined
Sep 26, 2004
Messages
2,973
Location
Georgia
Is there any way to change the default in case of a loss of A/F reading, maybe having the motor pull timing and dump fuel to like 10:1? Can a tuner change those parameters?

It seems like a situation that has the chance of happening again with nothing that you can do about it.
 

wrxman60

Premiere Wheelman
Established Member
Joined
Aug 25, 2008
Messages
483
Location
Philly
I purchased O2 extentions from LFP, does anyone know off the top of their head if they are from Casper Electronics? If not, I'll call Mark @ LFP
 

beefcake

Authorized Vendor
Authorized Vendor
Joined
May 16, 2001
Messages
8,986
Location
Cincinnati, OH
I purchased O2 extentions from LFP, does anyone know off the top of their head if they are from Casper Electronics? If not, I'll call Mark @ LFP

Just about everyone uses caspers stuff.

easiest way to tell. look at the connector. if where the 6 holes are for the 02 to plug in (both ends) are not gold at the tips, don't use em.

you'll know right away looking at it what i mean
 

beefcake

Authorized Vendor
Authorized Vendor
Joined
May 16, 2001
Messages
8,986
Location
Cincinnati, OH
here are all the pistons. some say it could have been gas, etc..



but,



only the 4 pistons on bank 2 are damaged, along with a bent rod. I know gas doesn't pick which side of the motor to send bad gas too. lol

IMAG0247.jpg


IMAG0249.jpg


IMAG0248.jpg


IMAG0243.jpg


IMAG0245.jpg


IMAG0244.jpg
 

Jimmysidecarr

Semi user friendly
Established Member
Joined
Sep 15, 2003
Messages
14,395
Location
Spring, Texas, United States
I am very encouraged to see such a thorough Engine Forensics search done on this car.

Way too many people just throw a new engine in and do it all over again.:nonono:

When stuff breaks it is absolutely essential that we find out WHY!

Great detective work!:rockon::beer:
 

Users who are viewing this thread



Top