If you are deleted, you absolutely can.
Bucking, Hesitation and Poor Economy Fix - Cleaned EGR and Intake (throttle) Valve
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Cleaned my throttle body,egr and maf sensor.Small improvement in cold start sputtering but far from a fix.There is something else going on with these cars.Mine has 36,000 miles on it.Has been doing this since about the time I got the latest nox sensor/reprogram done.
Niebs6.2---You quoted " I was pleased with the improvement in performance, but the car was still bucking, mostly first thing in the morning. " My car was doing the same even after cleaning the MAF,EGR and throttle body.Dealer finally figured out with the help from GM that the intake valves were caked with carbon.The fix is to remove the head and clean/recondition it along with cleaning the intake manifold (that part i'm assuming but the head is for sure).Mine was doing exactly what you describe,first morning start,stumbling and missing,worst when you first put it in reverse or drive and sit there with the brakes on.Fuel mileage was slowly getting worse,stumbling etc. goes away when engine warms up and runs smooth.No check engine light but dealer said they logged multiple misfire codes with their scanner,i guess those codes are stored but no check engine light.My cheap code scanner did not show anything.
Hey oreo382,
I've been following along on this topic since my initial post as my problem has returned. It has been getting pretty bad the last couple months. I've actually had it stall on me and when i went to crank it over, it sounded like it had poor compression - i suspect this is from bits of carbon breaking off and preventing a seal around the valve seat. So to me, your diagnosis makes sense. Too bad its such a big job (probably expensive too). Any suggestions on an intermediate fix ?
GM has some kind of system where they spray cleaner into the intake,let it sit for a couple hours then put some stuff in the gas tank.Not sure if thats just for gas engines though.I'd be scared to hydrolock the engine doing that.They say if no improvement do it a second time.Sounds like a bandaid or for lightly carboned engines at best.My dealership went straight for removal of the head,not sure if the put a scope in the intake before coming up with removing and cleaning.GM may have suggested removal right off.I may get it back this week and i'll try and find out the cost.I see you have about 60K miles,80% highway driving.I have 40K miles,mostly city.Do you live in a cold climate area like I do (Winnipeg,Canada)?
I'd like to know what that 2nd emission reflash actually entailed.
I'd like to know what that 2nd emission reflash actually entailed.
Sounds like Seafoam.
**** takes all sorts of carbon buildup off, and makes your vehicle appear that it is on fire when you go for a "spirited" drive after.
Should still work for a diesel, I'd think, as you suck it in through a vacuum hose. But yours may very well have been past what could have been removed even by Seafoam.
**** takes all sorts of carbon buildup off, and makes your vehicle appear that it is on fire when you go for a "spirited" drive after.
Should still work for a diesel, I'd think, as you suck it in through a vacuum hose. But yours may very well have been past what could have been removed even by Seafoam.
That BG system is like the one GM uses.They don't specifically say intake valves,makes me wonder how effective it is.In my case GM said r and r the head,no mention of using this method.
Update----Dealer called to say car was fixed.Picked it up and had check engine light immediately.Wheeled back in and told service advisor.He quizzed the mechanics and they said,oh yeah,one of the glow plugs is defective,its on order and will call you when its in.Due to warm weather its ok to drive.With that went on my way for a short highway drive.Pulled into the condo parking spot and pulled the engine cover to see if they broke off the glow plug,was greeted by a hissing sound coming from the injector area.Closer inspection revealed fuel leaking out and bubbling in the fuel injector well in the head.Back to the dealer,checked by them and confirmed,no driving due to safety hazard.Will have to order a new one.The saga continues.In addition I asked the advisor what the cost was so far.He said the cost he has is lower than what someone would pay out of pocket.Dealers cost $2400.00,he said at least $3500.00 for a regular customer.
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They charged you $2400??
No its all warranty work.That number is what the dealership charges back to GM for the work,for parts and labor.As I said the advisor said if a person had to do this not under warranty it would have cost them around $3500.00.So it seems that due to EGR mixed with PCV gasses and city driving is death to these cars.Not to mention most diesel fuel that has low cetane and no Top Tier cleaners. Its too bad,when I bought it what won me over was the engine,torquey,felt like driving a big V8,nice quiet ride,felt like a much bigger car.It looks like this diesel isn't the only one with carbon problems,lots of GDI gas engines with this problem.Some have gone to dual injection systems to try and stop the issue,Toyota for one.
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That brings up an interesting question: how have diesel engines dealt with this all along? GDI is new, but diesels have always been DI ; how have they avoided carbon buildup on the valves?
Sorry if that's rhetorical, but maybe there's something to borrow for the gas engines.
Doug
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There are past diesels that have carbon problems,mercedes comes to mind and I think some Volkswagens and maybe others.Emissions equipment,bad engineering,fuel that hasn't kept up with these issues.They are now getting into top tier diesel fuel like they did with gasoline.Gas engines were carboning the valves even with port fuel injection due to lack of cleaners in the fuel.Time for oil companies to step up and give the U.S. and Canada higher quality Ie: higher cetane and top tier diesel countrywide.
After reading through this thread, I decided to clean my throttle valve because I had noticed the slight bucking at low speeds like in parking lots over the past four months. Three months ago I had to have my Cruze towed to a shop because it would crank and start but not run for more than a second. The shop replaced the EGR valve becasue it had become stuck due to the carbon buildup and would not let the engine run.
Now that I have seen first-hand what the EGR and valve train vent are doing to my intake, I want to put a stop to it. I have seen links to the Oz tuner and KermaTDI tuner and am a little confused about what each are capable of. Currently I have a bone stock (besides cosmetics) diesel that I want to delete while keeping the power gains in a safe range and the sound level near stock. What are my options?
Edit: 82,000 miles with unknown history before July 2018 when I purchased it from its second owner.
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Now that I have seen first-hand what the EGR and valve train vent are doing to my intake, I want to put a stop to it. I have seen links to the Oz tuner and KermaTDI tuner and am a little confused about what each are capable of. Currently I have a bone stock (besides cosmetics) diesel that I want to delete while keeping the power gains in a safe range and the sound level near stock. What are my options?
Edit: 82,000 miles with unknown history before July 2018 when I purchased it from its second owner.
That first picture should be enough to convince anyone to get rid of the egr.Brutal,you should send that picture to Chevrolet,not that they will do anything.BTW,how does it run when you first start it after sitting overnite and put it in gear? Does it stumble and miss?
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Ugly, but cleanable/repairable for both at little cost right. How many cleans would it take to recoup the $1200+ you will throw away in the delete/tune on a car that already has close to 100K Miles. A little bit of maintenance every couple of years. But the DEF reservoir itself costs $500 plus you say. I replaced it myself for less than $200 in less than an hour. If you are marginally mechanically inclined this should be a no brainer if you are not looking for the performance boost (which you can get with just a tune at less than half the cost. I won't even go into the environmental footprint (though so small some might say 
) . These of course are my personal opinions.
) . These of course are my personal opinions.The car ran perfect before the cleaning. No hesitation when starting or driving, not even in the negative temperatures last winter here in Michigan.
I would recommend just having the map 0'd and leaving it in place. It will be closed 100% of the time anyways so removing it adds no benefit to the existing delete/tune. It does however benefit the manufacturer of the block off plates
I had a Smart fortwo diesel once, and I debated removing the EGR. Fortunately there was a long cool run of piping between the EGR and the engine that, if you were lucky, would clog up before the EGR valve did. It was said if you hit 50,000 km without the CEL going on for the EGR then it never would because the car deleted its self upstream haha. I removed one end of the pipe to verify, it was indeed plugged solid but the valve still moved freely which convinced the car all was well.
That BG service is known to erode turbo bearings.
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