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Posted
58 minutes ago, starman8tdc said:

 

 

Do you know if your engine has direct injection or port injection? If its direct injection, then the install time would be a bit longer, but still - the bill is extremely high. Your right, the dealership charges a lot. I'm glad to hear that you didn't have to pay for it. 

 

 

It is direct injection

Posted
57 minutes ago, cpttimerestraint said:

$1,800 is the going price by the time you get 8 injectors, all the extra seals and gaskets required and the labor to really it all apart.

Sent from my Moto G (5) Plus using Tapatalk
 

But you have r&r injectors twice. Plus diag twice.

Posted

So we picked up the car on Friday.
I was told that the fuel injectors they installed was bad out of the box. All the talk about carbon on cylinders and blah blah blah was just that imo.

They “said” they replaced the 2 injectors they just replaced..... I find that hard to believe but.... we drove the car home and the light didn’t come on or spit or sputter at this point.

Posted
On 7/10/2018 at 2:24 PM, YJSONLY said:

Sooo I stopped by today because I had to get something out of the car. No call just showed up.

Talked to the mechanic myself.... said they have test for leak down test and it all checked out.

Says that it is having a miss but not sending a code for a miss. Only a fuel trim code showing.

Had to dig around. Found that the number 7 plug was gapped/smashed due to carbon build up on top of the cylinder. Said he put new plug in. Ran vehicle and they same code. When pulled new plug was back to close gapping. Said that need top of cylinders needed cleaned of carbon.

Sorry dude but the spark plug gap doesn't get "smashed" from carbon build up. If spark plug gap is truly "smashed" you have a mechanical failure of some sort. I am not buying that explanation.

Posted
Sorry dude but the spark plug gap doesn't get "smashed" from carbon build up. If spark plug gap is truly "smashed" you have a mechanical failure of some sort. I am not buying that explanation.


Like I said I think they screwed up something when installing new injectors. Ie bad seal, o ring or gasket....
Posted

So I really drove it myself today vs my wife. And at idle in park the rpm gauge is not consistent. Varies about a solid needle width. This normal?

 

Posted
I would pull the plug on that particular dealer. I think a fresh set of eyes on the problem is warranted at this point. Maybe another Chevy dealer tech has seen this problem before? 


And more money out of my pocket to boot tooo. Might come down to that tho. This isn’t a small dealer either.
Posted
45 minutes ago, YJSONLY said:

 


And more money out of my pocket to boot tooo. Might come down to that tho. This isn’t a small dealer either.

 

Sometimes the smaller dealers are way better.

Posted
Sometimes the smaller dealers are way better.


Ha. The other small dealer I took it to. Didn’t even have a tech.... yes a Chevy dealer that had zero techs.
Posted
On 7/12/2018 at 10:59 PM, starman8tdc said:

 

 

 

    4.6 hours? WOW! I have never seen any injectors that were not easily accessible. Learn something every day. Any chance you could upload some pics or repair instructions? 

 

    As for the more expensive injectors, I would not go that route - but that's just me. I have had good luck with the cheap injectors on many rigs. 

If you haven't done a direct injection repair yet I suggest you watch some videos on it or take a small class. The pressures of the systems are very high, it's important to bleed off the system before you start working on it (pressures can reach 2,000 psi during operation). The high pressure fuel pump is very expensive, so be careful not to damage it when you remove it. And the injectors are high voltage (if I remember correctly) and they are probably a pain to remove because they are in the cylinder and head...I'm trying to imagine how bad it'd be to remove with over 100,000 miles on them. Yikes.

 

Very few systems use BOTH the direct and port injection together, although that may change with all the carbon issues on the valves, but that is expensive for manufacturers (and they care more about profit than reliability).

 

Honestly I haven't heard about many problems with the actual systems themselves, more with the carbon buildup on valves than anything else. I used to own a direct injected Lexus...178,000 miles and not one single issue. In fact I've seen cars with 300,000 without issue.

 

pretty surprised to hear the GM injectors failing at low mileage....even more surprised it's  not covered under warranty. These systems aren't exactly "new" anymore, every car on the road uses them now.

  • Like 1
Posted
36 minutes ago, Doublebase said:

If you haven't done a direct injection repair yet I suggest you watch some videos on it or take a small class. The pressures of the systems are very high, it's important to bleed off the system before you start working on it (pressures can reach 2,000 psi during operation). The high pressure fuel pump is very expensive, so be careful not to damage it when you remove it. And the injectors are high voltage (if I remember correctly) and they are probably a pain to remove because they are in the cylinder and head...I'm trying to imagine how bad it'd be to remove with over 100,000 miles on them. Yikes.

 

Very few systems use BOTH the direct and port injection together, although that may change with all the carbon issues on the valves, but that is expensive for manufacturers (and they care more about profit than reliability).

 

Honestly I haven't heard about many problems with the actual systems themselves, more with the carbon buildup on valves than anything else. I used to own a direct injected Lexus...178,000 miles and not one single issue. In fact I've seen cars with 300,000 without issue.

 

pretty surprised to hear the GM injectors failing at low mileage....even more surprised it's  not covered under warranty. These systems aren't exactly "new" anymore, every car on the road uses them now.

 

 

   Good info, thanks for posting. 

 

   From what I have read, the direct injections systems are definitely superior to all the predecessors. I have been working on various cars for decades, but I have not had any issues come up with that particular fuel system. 

 

   I will definitely study the system well before taking one apart. 

 

 

 

 

 

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