GMC Acadia Forum banner

1 - 15 of 15 Posts

·
Registered
Joined
·
75 Posts
Discussion Starter #1 (Edited)
Ticking injector at cylinder 6.

I’ve unplugged the injector while running and the other injectors are quiet. The engine runs relatively the same without it.

Is it normal for the injector @ cylinder 6 to tick? I’ve read here it’s a direct injection motor so some ticking is normal? But this is the only injector that ticks. It’s a steady tick.

I’m mentioning all this because upon every start I feel what I think is a pull back on the timing. It seems my rpms drop before the engine warms up on a cold start (10-15 seconds).

I recently got a CEL upon heavy acceleration (misfire on cylinder 3). About once a month I’ll get a flashing CEL indicating random misfires but the CEL always clears its self. The only CELs that throw are misfires.

I also get lack of power on inclines below 3000rpm. Once at 3k you can feel the power sort of just wake up.

Not sure if the two at all could be related.

The car has new coils/splugs 30k miles ago. Car is now at 130k miles.

I’ve checked for vacuum leaks by spraying brake cleaner (dangerous I know) on a cold engine but there is no RPM change.

What should be my next step? Fuel pressure gauge?
 

·
Super Moderator
Joined
·
18,629 Posts
Sounds you hear from the injectors should be nearly the same on all 6 cylinders. If there's no obvious change in the way the engine runs with #6 unplugged, suspect something is wrong there.
 

·
Registered
Joined
·
75 Posts
Discussion Starter #3
Sounds you hear from the injectors should be nearly the same on all 6 cylinders. If there's no obvious change in the way the engine runs with #6 unplugged, suspect something is wrong there.
Ok yeah, it’s only the one that’s making the ticking. You can feel the tick when touching the injector harness.
 

·
Super Moderator
Joined
·
18,629 Posts
If it hasn't been done recently, put a bottle of injector cleaner in the next tank of fuel and run with it, or get the injectors cleaned (DIY kits available). Change for the better could be realized if the problem is just a dirty injector. If not, move on to step two - suspect the injector needs to be replaced!
 

·
Registered
Joined
·
329 Posts
Ok yeah, it’s only the one that’s making the ticking. You can feel the tick when touching the injector harness.
Techron Concentrate Plus (contains more PEA active ingredient) works well to clean the injectors.
Note: NOT to be confused with the less powerful Techron Injector Cleaner.
The 20oz (or two 12 oz) Techron Concentrate Plus into a full gas tank may help followed by another dose in a full tank of gas if you've never added any fuel system cleaner. Run each treated tank of gas near empty . . . maybe at least down to 1/8 left in the tank before filling again.
EDIT: Autozone now has a Buy 1 Get 1 Free on the 12oz size. So buying Two 12oz containers is cheaper that buying the 20oz container. Buy 4 and you'll be good to go.

https://www.chevronlubricants.com/en_us/home/products/by_brand/techron.html?gclid=EAIaIQobChMIisSgqtKR5QIVXR-tBh0UmgbwEAAYASAAEgKzjvD_BwE&mkwid=sUv8XezBL_386235166057_techron_p_c&mtid=744bv356395&slid=&product_id=


 

·
Registered
Joined
·
329 Posts
Yup . . already read that article but didn't want to put too much in a posting.
And. Techron is right up there as a top choice as it has been for quite a few years now.
 

·
Super Moderator
Joined
·
18,629 Posts
Read the MSDS for any of those products and you'll see a surprising equality.
 

·
Registered
Joined
·
329 Posts
I have. . . and reviewed such products for many years now. Especially since the introduction of Gasoline Direct Injection. PEA is one of the major ingredients as many already know.
 

·
Registered
Joined
·
75 Posts
Discussion Starter #10
If it hasn't been done recently, put a bottle of injector cleaner in the next tank of fuel and run with it, or get the injectors cleaned. Change for the better could be realized if the problem is just a dirty injector. If not, move on to step two - suspect the injector needs to be replaced!
Do all of the shop injector cleaners take off the injectors to clean/test? Or is it standard to just hook up cleaner to the fuel rail?

I’d prefer the clean and test, I’m assuming it’s more money?

I’ve used the Techron fuel system cleaner a few times over past month. Didn’t really notice anything.

Techron Complete Feul System Concentrate (contains more PEA active ingredient) works well to clean the injectors.
Note: NOT to be confused with the less powerful Techron Injector Cleaner.
The 20oz Techron Complete Fuel System Cleaner into a full gas tank may help followed by another dose in a full tank of gas if you've never added any fuel system cleaner. Run each treated tank of gas near empty . . . maybe at least down to 1/8 left in the tank before filling again.
EDIT: Autozone now has a But 1 Get 1 Free on the 12oz size. So buying Two 12oz containers is cheaper that buying the 20oz container. Buy 4 and you'll be good to go.

https://www.chevronlubricants.com/en_us/home/products/by_brand/techron.html?gclid=EAIaIQobChMIisSgqtKR5QIVXR-tBh0UmgbwEAAYASAAEgKzjvD_BwE&mkwid=sUv8XezBL_386235166057_techron_p_c&mtid=744bv356395&slid=&product_id=
Thanks, I actually did the buy one get one a month ago at AutoZone. Good deal.
 

·
Registered
Joined
·
329 Posts
I’ve used the Techron fuel system cleaner a few times over past month. Didn’t really notice anything.


Thanks, I actually did the buy one get one a month ago at AutoZone. Good deal.
The key with Techron is to put enough in the tank to be effective as the bottle indicates. A 12 oz bottle is for smaller cars with 10 to 12 gallon gas tanks. If a vehicle has an 18 to +20 gallon tank, the 20 oz bottle or Two 12 oz bottles should be used.
If enough is not present in the gas tank, then it will not do a whole lot. Also, once enough is in the tank, the tank should be run near empty before adding more gasoline.
Techron or any of these is not so effective if the engine has a lot of miles, injectors may be worn or cleaners were never used along the way. Once and injector is clogged or really clogged with combustion chamber contaminates, not much will help usually except for replacement.
 

·
Super Moderator
Joined
·
18,629 Posts
Do all of the shop injector cleaners take off the injectors to clean/test? Or is it standard to just hook up cleaner to the fuel rail?

I’d prefer the clean and test, I’m assuming it’s more money?
Shops will clean the injectors while they're on the engine as a rule. Remove, clean, and test isn't SOP. That will be $$$!
 

·
Registered
Joined
·
75 Posts
Discussion Starter #13 (Edited)
Shops will clean the injectors while they're on the engine as a rule. Remove, clean, and test isn't SOP. That will be $$$!
That’s what I figured. And it looks like you gotta take off the intake manifold to access the injectors.

Kinda sucks to be honest. The cost for cleaning will be the same as replacing the injector if I did everything myself.

With my luck I’ll pay to clean it and it still will need to be replaced.

Little side note, the previous owner use to go to Valvoline to get oil changes and I asked to see the service history and the previous owner did a fuel system clean maybe at 50k miles.

Really hoping it was for a different reason and not related.

Btw, what is SOP?

Perhaps I’ll make a YouTube video of the ticking/idle drop, before spending money on the cleaning. I find it strange how it ticks very rapidly while inserting the wire harness.
 

·
Super Moderator
Joined
·
18,629 Posts
SOP is usually forcing a high-grade injector cleaner through the injectors via the fuel rail while triggering each injector, then running the engine vigorously to clear out the cleaner.
 

·
Registered
Joined
·
329 Posts
Btw, what is SOP?

Perhaps I’ll make a YouTube video of the ticking/idle drop, before spending money on the cleaning. I find it strange how it ticks very rapidly while inserting the wire harness.
SOP - - - Standard Operating Procedure or similar term.
 
1 - 15 of 15 Posts
Top