kombifan

mcoady1

Alrighty have the car back in hand and have put Techron additive in for one total tank, however it was a 700 mile highway trip so may not have been the best cleaning environment for the PEA. It's still misfiring but mainly only at idle and under some mainly low end acceleration. CEL turned off although the codes are stored for misfires (Cylinder 1, 3, 7). I just put in Gumout Regane with a tank of Chevron gas. I'll have lots of city driving so hoping that will help the PEA really do it's thing. I will update back after a tank or two. May try other brands user suggested next tank if not much improvement.

"The tumble flap shafts stick in the actuated position" is what I see on my report, so looks like the intake repair may be fine. If there are no other internal manifold parts that commonly break with age other than the tumbler flap I see no reason to replace the entire manifold. I see other users express concerns about clogging inside manifold and other internal plastic pieces breaking, but I can't seem to find the details of which parts break. If anyone feels like a replacement manifold is advisable over the aluminum repair kit let me know. Seems like replacement may be dealer/mechanic propoganda working.

kombifan

eric_in_sd

You learn fast, young Jedi. Good job on the flap analysis. Note you can get a cheap usb borescope to check the position of the flap. I'm pretty sure the PARTZ WIL BREAK N UR ENGINE WILL DIEZZZ stuff is bull, but I do not know for sure.
Definitely try the prolonged idling. The engine uses very little gas when idling, so the detergent will move through slowly and get warm. It doesn't hurt the motor to run it at idle, and the only downside to running the additive through in normal driving is you throw most out the tailpipe. The additive-containing gasolines are near useless for this same reason; you're much better off taking the same detergent and running it through in a prolonged idle once every couple of years or so. Those gasolines don't contain much PEA anyway. You'll save a bunch of money at the pump. Use it to buy beer, which we will all agree is a better use of the funds.

P.S. If I were you, I'd start buying up expected spare parts. I have a bunch of coils I've scrounged off Amazon Warehouse, a fuel injector, a serpentine belt, and so on.

mcoady1

Kombifan- It all started out with a little vibration/shuttering under load at RPM's (I wasn't sure what it was at the time). Then it progressed into a noticeable misfire without CEL where you could clearly feel the misfire at traffic lights. Then it went full blown misfires with flashing CEL/shaking etc. It's better now but you can feel the misfire occasionally especially at idle. Idle isn't necessary too rough, but moreso somewhat noisy from exhaust. I did have the issue with air filter/MAF assembly not being properly put on, but that threw a lean code and I fixed it (I also caused it ha).

Chevron is Tier 1 and is pricey. I however was in the middle of nowhere Texas and since a known Tier1 I stuck with that gas station. There a Circle K near my house with Shell so will probably stick to that as it's reasonable and Tier 1.

Thanks Eric! I already have a coil and an Arnott front strut shelved in my garage (I found two for $400 off eBay - wonder if the guy robbed a mechanic!) after owning the car for two months. Seems like I may need more. Will idle some more to let the detergent sit. This car may drive me straight to the hard liquor rather than beer!

mcoady1

**Update**
I am on Tank 3 of injector cleaner with tank 95% full. Tank 1 was all highway so didn't have noticeable cleaning results. Tank 2 was primarily city driving and misfire/performance did get noticeably better as time went on. Tank 3 seems to be on the right track also, the Gumout Regane may do the trick. Two bottles at Walmart are $10.77 total so not bad. There is still an occasional misfire under load at low RPM's and at idle, but not violent by any means. My scanner says it's Cylinder 1 and 7 still with the misfire, but primarily Cylinder 7. I've let it idle for hours at a time on multiple occasions. One time an Airmatic Malfunction light appeared after hour or so of idling but ended up going away, hoping this was electrical gremlin as it was over a week ago and hasn't reappeared with lots of driving. The car will lift to raised level within 10 seconds also, do doubt it is compressor. I tested the Airmatic relay and fuse and both fine.

The accelerator pedal at time seems to be stiffer than others, i.e. pedal resistance. This morning it was very pleasant to push other times feels like I'm driving my family's old '87 300TD. Perhaps I should try to lubricate the throttle linkage or pedal assembly. Don't think this has anything to do with intake flap?? I know I need to fix this to rule out but am scrapped for time. Any thoughts here?

eric_in_sd

I'd say you probably fixed whatever gummed fuel injector issue you had. Hard to tell for sure, of course, but if you have eight performing fuel injectors and you ran detergent through them slowly, then they presumably got pretty clean. I'd say keep an eye on it. Post the actual misfire data - are we talking 0301 & 0307?
I'm not familiar with the tumble flap ramifications, but low rpm misfire seems like a possibility, as the motor could be expecting swirled airflow (or whatever the flap does when closed) and it's getting straight, if stuck open.

Air suspension is a constant struggle in these things. Possibly you have a slow leak and it didn't get the suspension deflection - because it was parked, idling - to trigger the reinflation. Lift the suspension with your off-road button and hose down the airbags with soapy water. If you see stoner spit (as in the fine foam that forms at the corners of pot smokers' mouths), that's your leak. They tend to leak at the fold, so you'll see it slower but more easily when the suspension is lifted.

Betcha anything it's the problem. Can't you muck the flap linkage, like with a wire tie, to get it out of the way?

mcoady1

Originally 0301, 0307, now only 0301 registering. Misfire data from app is attached.

Will do, this car seems to be on pot half the time. It is amazing that I could literally watch the strut deflate within 30 seconds when I had a leak and this would not trigger error code, but a slow leak while idling may trigger error message. Hans and Helmut could have designed the system with better onboard diagnostics.

I'll try to rig it this weekend.

mcoady1

mcoady1

eric_in_sd

mcoady1

I reset the code but still seems to be running rough, only P0301 is reading. The OBD Fusion App for iPhone offers Mode 06, where I can view each cylinder's misfire counts for the last/current driving cycle vs EWMA (Exponential Weighted Moving Average) misfire counts for last ten driving cycles. 13 would mean on average 13 misfires per driving cycle average, which doesn't sound like much but the misfires were felt. Not sure where the threshold is where the P03xx will jump in, but the Model 06 is great for looking at misfires before code is thrown. Maybe throw on some dieletric grease to boot?

Tumble flap is still messed up and I do need to fix that, I guess I haven't been as concentrated on that issue since I've noticed many other users claim they barely noticed performance change when the tumbler flap needed replacement. I will plan to fix soon just to rule this out.

This morning at first start it cranked then killed immediately. When I started second time and gave it some gas it cranked right up then idled rough with the misfires. It's been slightly slow to start a few times within the past month; maybe once every other week, but this is first start and kill. I read BlownV8 mentioned his camshaft position sensor caused sudden misfire condition, albeit at a much higher mileage (I'm only at +/- 87k), but with similar symptoms. The slow crank is symptom of camshaft position sensor, but there is no P0340 code. I guess the shuttering and other symptoms I had could have been from failing CPS also, but not strong enough theory for me to throw money at just yet.

Good point with ethanol-free gas, but the main trigger to the misfire hell was removing the plug/coil boot, there were no codes before. I just installed plug down below with magnetic extension, same thing happened and remains with two plugs and two coils. Saw you had similar issue and even replaced/moved around injector(s) and boot(s), how'd you finally resolve the misfire? OBD reset or another kind of reset?

mcoady1

Alright late follow up here, but issue resolved! The d*** Denso Iridium spark plugs I used apparently were causing the misfires. Strange it was only on a few of them, but swap to NGK resolved all misfires.
Ironically this was found by my back yard mechanic rather than the Euro mechanic with Star Diagnostic. The car still shutters at low RPM's when accelerating but may be more transmission related than engine contrary to what I originally thought.

eric_in_sd

You're likely jumping to conclusions without patiently eliminating variables. Did you fix the intake manifold? I've never heard of the 722.9 transmission causing a shuddering feeling, unless it's about to vomit a slurry of metal shavings and 236.15 fluid.

I'm a little puzzled by people's affection for non Bosch plugs. The Bosch come pre-gapped and everything. Is there something I'm missing?

mcoady1

Not sure why mechanic chose NGK although I used Bosch in my wife's X3. At this point I was just ready for an engine firing on all cylinders.

I did fix the manifold so we can rule that out. Sometimes when I let off gas car can be a little jerky disengaging, i.e. torque converter. The 722.9 needs a full fluid flush with including torque converter, right? When I bought the vehicle the only thing not clear on service history was if trans fluid change was done at recommended 40K. Now at 87K.

Shutter is nothing too alarming and is intermittent.

eric_in_sd

Good. If you haven't already, post your findings and fix on the manifold. Pay it forward.

Absolutely get your transmission serviced. Have them do a service, in which they drop the pan, change the filter, inspect for debris, etc., and inspect the fluid. This changes about half the fluid. It's okay to just dilute the old fluid with new - unless the old fluid is filled with metal chunks, in which case it won't matter much anyway.

However, you'll want to base what you do next on the condition of the fluid. If it's black, that is, was not changed at 40k, as very often happens, you are in a precarious situation. You may find that updating the fluid makes the symptoms worse. See ChrisFix's video on this.

I had the fluid in mine flushed at 90k for the first time. Was black. Had a transmission service at 120k; they said all appeared fine, although there was a 0717 - turbine speed sensor - code stored. 9k miles later, it went boom. In fairness, I was not kind to that transmission, going offroading and such. So there basically was little to no warning. The shop might have installed bad oil, though they are reputable; more likely is that the trans was teetering on the edge.

There's a good thread on MBWorld about transmissions. Supposedly there's an upgraded bearing that certain shops will install in a rebuild, you can get good info if your shop uses a Star to reset the programs - it can tell you about clutch wear - and you should have it serviced every 30k.

kombifan

Henry Hemphill

Can you post the exact ones you had installed? My vehicle is doing the samething.

kombifan

mcoady1

Henry, not sure which plugs as my mechanic selected them but let me know if you should still need exact part number.

Eric, I will be sure to have transmission fluid/filter/gasket soon and see what the fluid looks like. My understanding it is possible that my 2011 could have the plagued conductor plate issue but is less likely than the early production GL's. I'm pretty easy on my transmission minus primarily city driving. Which part exactly blew on your transmission? When do the engine mounts and transmission mounts usually fail on these models? Seems if one of these failed the issue would be more consistent rather than intermittent.

Regarding intake manifold, I ordered rebuilt intake manifold from RMT (Rebuild Master Tech) since they offered rebuilt manifold cleaned out and with aluminum tumbler flap for roughly $400 (also includes manifold gasket). I ordered injector o-rings separately. Since I plan on keeping this car for a while I found the refurbished manifold worth the value as I am extremely crunch for time now (ie. no time to remove manifold then decide whether flap repair only vs.entire replacement). I payed $50 core which RMT promptly refunded when I sent my old manifold back. My mechanic did the repair rather than myself so I can't comment on the exact ins and out of the repair, but he did comment that the vacuum actuator for the tumbler flap was broken. To be honest there is not a huge difference in performance.

Had secondary air injection malfunction (P0410) the day after I got car back but cleared it and it came back once but has not returned in two weeks. The car was slow to start when cold also at first but that has gone away also.

eric_in_sd

You'll see it throw error codes re: the conductor plate / turbine sensor / etc.
Couldn't tell you. Pretty much everything, lol. I lost 3rd and 4th gears, if memory serves me correctly. My understanding is that it's shifting that wears those things out; the drive-by-wire throttle takes a lot of the load off (hence the smoothness of the shifts) but still there's wear. And, particularly, wear with messed up fluid.
Get that pan dropped and the fluid checked. Then decide what contingency plan to put in place.
Motor mounts leak, so that's easy to diagnose. They don't seem to be a super high failure rate item, though. Mine are fine at 150K.

As alx put it, that truck ages well. It's hard to put your finger on it, but mine drives great, the clunking stabilizer link notwithstanding.

Sometimes it's flaky electrical. Mine threw one 410; the mechanic diagnosed it, and I balked at the price, so I waited. I still have the pump and relay sitting on my shelf, and the error has not recurred. Go figure.

Watch out for starter wear. The truck cranks slow, and it has a surprising effect on its ability to start. Possibly the computer doesn't start spraying fuel until the rpms get above a certain threshold; I don't know. I changed my starter and wish I had much earlier.

Mikchek

This post sure detoured from the original title lol...

Can anybody tell me if the P0422 error is for the Cat on the left side or the cat on the right side?

eric_in_sd

P0420 Catalyst System Efficiency Below Threshold (Bank 1)
P0421 Warm Up Catalyst Efficiency Below Threshold (Bank 1)
P0422 Main Catalyst Efficiency Below Threshold (Bank 1)
P0423 Heated Catalyst Efficiency Below Threshold (Bank 1)
P0424 Heated Catalyst Temperature Below Threshold (Bank 1)

I didn't easily find the difference between 422 and 420 - that is, exactly what behavior in the system it is responding to.

Bank 1 is the bank containing cylinder 1. In the left-hand-drive (North American) GL, that is the passenger side. Avoid using the terms left side and right side because - is it referring to when you're sitting in the driver's seat? Or facing the engine from the front?