2012 Tahoe needs a new engine

[Nighthawkpearl]

I took it to auto shop due to p0300 code. Misfire. Today they called me and said it needs a new engine due to no compression? What does it mean? Like lifter things?

 

[B-train]

Maybe a bad lifter which means low compression. Or a cam that is toast and can mean low compression.

I'd ask how they came to that conclusion. What data can they show you, other than a code reader? Without more info, it sounds like a worse case jump to conclusions scenario with the highest profit margin

 

[Nighthawkpearl]

ok I will ask them about it tomorrow, like do I need Afm delete if so where can I find best Afm delete parts?

 

[Nighthawkpearl]

Maybe a bad lifter which means low compression. Or a cam that is toast and can mean low compression.

I'd ask how they came to that conclusion. What data can they show you, other than a code reader? Without more info, it sounds like a worse case jump to conclusions scenario with the highest profit margin

They said that there is no compression on 7 cylinder and they wouldn’t go deeply, just simple get a new engine. So I took it to different auto shop who can specialize to see if lifter, cam or valve is bad.

 

[Fless]

They said that there is no compression on 7 cylinder and they wouldn’t go deeply, just simple get a new engine. So I took it to different auto shop who can specialize to see if lifter, cam or valve is bad.

Good, maybe the new shop will diagnose it deeper. It could just be a valve staying open for some reason. The remedy for that is much different from needing a new engine.

 

[Nighthawkpearl]

again, they just called and said the same thing. They won’t open the head to see. I don’t understand what diagnosis I pay for?

 

[B-train]

Pulling a valve cover is easy to do......don't need to pull a head. With the VC off, turn the motor by hand. It will tell if it's simple like @Fless mentioned. If it's not, then you have a decision to make.

How many miles on the truck? Is it in good shape and has maintenance been kept up? Is it rusty (salt state vehicle). These are questions I'd ask myself before determining how to proceed with an engine replacement.

 

[Nighthawkpearl]

Pulling a valve cover is easy to do......don't need to pull a head. With the VC off, turn the motor by hand. It will tell if it's simple like @Fless mentioned. If it's not, then you have a decision to make.

How many miles on the truck? Is it in good shape and has maintenance been kept up? Is it rusty (salt state vehicle). These are questions I'd ask myself before determining how to proceed with an engine replacement.

Dude, my suv arrived at my home via towing and I suddenly open the value cover and found out its value spring(itself) is loosing on cylinder 7 . Is that possibly problem?

about 80k miles on it and good maintenance.

 

[strutaeng]

Dude, my suv arrived at my home via towing and I suddenly open the value cover and found out its value spring(itself) is loosing on cylinder 7 . Is that possibly problem?

about 80k miles on it and good maintenance.

What do you mean? Can you post a photo of what you are seeing so there's no misinterpretation?

 

[Nighthawkpearl]

I uploaded a video on YouTube. Just you know I am Deaf and not good at English.

Here YouTube link

 

[B-train]

I'm going to go with a bad lifter. There should be tension from the pushrod on the rocker arm and spring.

 

[strutaeng]

Well, that's a problem...


Seems like too much slack. The spring is not broken, correct?

 

[Nighthawkpearl]

It’s spring broken., not lifter since the rocker works fine. I am gonna replace the spring and will let you know how it goes.

 

[j91z28d1]

wow. good find. I'm glad you didn't listen to 2 shops and replace the engine.

it's such a shame what shops have become. can't even pull a valve come and check for a broken valve spring these days.
ugh.

 

[Nighthawkpearl]

wow. good find. I'm glad you didn't listen to 2 shops and replace the engine.

it's such a shame what shops have become. can't even pull a valve come and check for a broken valve spring these days.
ugh.

Yeah exactly, they screwed up my wife’s emotions.its hard to trust the shops. If it’s an auto repair shop, they are supposed to find out what causes. Both shops won’t open the engine to see what’s wrong. I paid for like $200 total for both shops for diagnostics.

 

[strutaeng]

I was going to suggest that you find a shop to do a leak-down test, which would have revealed where the air was escaping (intake, exhaust valve or piston rings.)

But you wisely found the source and seems like that was your problem.

Please keep us updated on the outcome.

 

[swathdiver]

Glad you did the right thing and looked at it yourself. Too many lazy losers and thieves out there.

 

[Dustin Jackson]

I had the same problem when the lifter failed in my Tahoe, no shop wanted to fix the problem they just wanted to throw a new motor in it and leave the AFM. I ended up fixing it myself and removing AFM parts on the process. That was about 20k miles ago still going strong

 

[R467X]

If it does indeed turnout to be just the spring, great. However, if you plan on keeping it, do yourself a favor and perform an AFM + VVT if you have that delete. Reach out to Michigan Motorsports or Texas speed, they'll email you all the parts you need. There are lots of videos online and plenty of support here if you get stuck.

I just did mine a number of months back and went through Michigan Motorsports. Can't recommend their service enough. They'd get back to me via email within 20 minutes most times 7 days a week.

You should be able to do this in 3-4 days if you work all day. Took me 2 weeks doing a few hours here and there.

 

[Nighthawkpearl]

I want to but maybe in the future when I have time and money. I am a full time father with 4 kids while my
Wife works full time but hopefully in the future. Thanks for tips!

I pulled the spring out and the spring is broken. Here the link.

Then I installed a new spring and new sparks plugs.

Put everything back on and it runs way better than before. My wife is so relieved.