Alh injection pump

[Nathan_og]

2 weeks ago my alh threw a p1562 quanity adjuster upper limit reached code with a check engine light and flashing glow plug light but ran perfect other wise.

Today after driving it to work and home when i went to start it up the rpm starting stuttering and it threw the glow plug and check engine light. I let the car warm up and it seems to drive fine but sometimes stutters at idle. sometimes it doset sometimes it does and sometimes its almost as if it wants to stall out. But its definitely stuttering a lot.

I did the hammer mod around 3 months ago to bring my iq from 1.8 to 3.2. At the time the seals didn't start leaking but now they have started to leak a decent amount.

Does this mean the pump may need a rebuild?

 

[JETaah]

Did the hammer mod help the shudder? I would think that IQ of 3.2 would have solved the typical slow-down shudder problem if you have stock injectors.
You at least need a new seal job be it by your hand, a TDI club guru's hand with experience on the procedure, or a Bosch repair facility (Diesel Fuel Injection Services in Portland, OR is my choice).

If the QA seal is leaking from disturbing it then the other seals are probably not far behind it.

 

[Mongler98]

no. not necessarily until we diagnose a few things.
shudder is from one thing and one thing only, not the right amount of fuel at the right time. unless were dealing with knock, but thats probably not going on here.
the IQ does not just move... so why was it down so low?
#1 Change those seals NOW. leaking fuel will destroy other things quickly.
#2, put the engine (from the crank bolt only) to TDC and verify that the cam and IP both Lock out and the flywheel is correctly aligned.
#3 check the timing graph and make sure you are within the upper and lower lines (use VCDS)
#4 make sure the fuel filter is serviced and no major air bubbles are present.

 

[BobnOH]

My first TDI (99.5 J) came from the factory with an IQ of around 1.8. Had some shudder, but only at idle.

 

[Mongler98]

My first TDI (99.5 J) came from the factory with an IQ of around 1.8. Had some shudder, but only at idle.

Just because it left the factory that way... you know there are issues with cars right off the assembled line. Vw has a very high number back then of pp100 or (problems per 100)

 

[94cobra2615]

Pull the top cover of the pump and check the QA sweep when u turn the key on engine off.
If it doesnt have full travel from the self test or isnt smooth when it sweeps-- most likely the QA needs cleaned inside.
You can use vcds to check the min/max voltages from the self test to see if they are not in spec.

 

[Nathan_og]

Did the hammer mod help the shudder? I would think that IQ of 3.2 would have solved the typical slow-down shudder problem if you have stock injectors.
You at least a new seal job be it by your hand, a TDI club guru's hand with experience on the procedure, or a Bosch repair facility (Diesel Fuel Injection Services in Portland, OR is my choice).

If the QA seal is leaking from disturbing it then the other seals are probably not far behind it.

I wasn't getting any shutter just too much smoke since i put .205 nozzles

 

[ts888]

I'm having similar issues as of Tuesday night. '03 ALH, car was running like a happy sewing machine until the last 30 feet coming into the driveway. Stumbled at idle when I pulled in the carport, then died. Started again, but was running a bit rough. Wednesday AM, started fine, ran well but about 50 feet down the driveway the CEL came on and GP light flashing. I did a 350+ mile drive last weekend, everything was perfect, not a stumble. Last fuel fill up was around the 6th of June, still plugging away on the same tank.

When I got to the shop I plugged in VCDS and I've got P1562. On the drive home for lunch I watched the IQ, it was about 3.5 at cold start, would go up into the 20's under load. Pulling into the carport to idle with a warm engine, idles at about 1.4-1.6. MAF and boost numbers are good, idle is about 900.

Based on what I know of this car's history, the pump has not been touched. All the paint is still intact, it is not visibly leaking and I know it's timed right because I'm only about 1800 miles out from the cylinder head/timing belt replacement.

After work today I'll continue diag. Rosstech wiki suggests some wiring checks, resistance check on N146. We shall see.

 

[KLXD]

Idunno off hand what that Code means so I'll throw this up: Maybe it's taken until now for the bad batch of fuel to saturate the filter?

Is everything stock? IQ seems low.

 

[ts888]

P1562 description is "Quantity adjuster (N146) Upper limit reached -- intermittent." In practice, upper limit is not the only thing that will register the fault.

When I got back to work the IQ at idle was dropping to .5 and below, so the variance in this case appears to be below the limit, not above.

I didn't work on it today. After I spent an hour wrestling the wheels off a wrecked Tesla so the doc who owns it can put the set on his other Tesla (I advised against it given the hit the wheel took, but he's a doctor dammit, he knows more than me), I found out I get to pull an 020 out of a Golf this weekend and try to rectify whatever the boss's kid did to the clutch that's making it not engage. I'm the janitor, I clean up everyone's messes.

 

[burpod]

For sanity sake check relief valve

 

[burpod]

I wasn't getting any shutter just too much smoke since i put .205 nozzles

The main reason why you get shudder down low is because timing/fueling is off. If you want to believe adjust IQ is enough, you can believe that. It all depends on the tune. Often it's too much advance.but advance is relative. If you're getting smoke, then it's likely not too much advance and thus no shudder.

 

[STDOUBT]

For sanity sake check relief valve

OK, in all my (nearly-daily) years here, I've never heard of a "relief valve" on a VE injection pump.
School me, broham.
FWIW I had the P1562 code once, and without symptoms (CEL, I think) - said a prayer, cleared it, never came back.
¯\_(ツ)_/¯

 

[BobnOH]

It's right on top, easy to check. They often come apart internally, can usually be slid back together. Have read of issues, but the thing doesn't seem to do much.

 

[Fahrvegnugen]

Keystone mod videos on google explain the valve. It can be bought for 50

 

[drew5250]

2 weeks ago my alh threw a p1562 quanity adjuster upper limit reached code with a check engine light and flashing glow plug light but ran perfect other wise.

Today after driving it to work and home when i went to start it up the rpm starting stuttering and it threw the glow plug and check engine light. I let the car warm up and it seems to drive fine but sometimes stutters at idle. sometimes it doset sometimes it does and sometimes its almost as if it wants to stall out. But its definitely stuttering a lot.

I did the hammer mod around 3 months ago to bring my iq from 1.8 to 3.2. At the time the seals didn't start leaking but now they have started to leak a decent amount.

Does this mean the pump may need a rebuild?

I highly recommend sealing the entire pump when you do the job. I developed a bad leak a few weeks ago, ordered a seal kit, but only replaced the seals that were leaking (both fuel quantity seals). Less than a week later, my pump head seal started leaking. I regret not replacing all them in one swift swoop. I'm running 76 renewable diesel, which advertises "high cetane" which is obviously desirable for fuel economy, power, and less smoke...but I have a feeling it might have something to do with all of my seals going out in such a short period of time.

 

[KLXD]

Yeahbut no matter how far the retainer backs out the relief can't come apart until you remove it. No clearance in there.

Whether backing out affects the "setting" or more importantly its basic funcfuncfunction I don't know.

 

[J_dude]

Yeahbut no matter how far the retainer backs out the relief can't come apart until you remove it. No clearance in there.

Whether backing out affects the "setting" or more importantly its basic funcfuncfunction I don't know.

I believe it does, from what I have read, but I have no real world experience with that other than pulling mine out and tapping the roll pin back in, it hadn’t come out very far.

 

[ts888]

Today I made a conscious effort to avoid letting the engine idle. No P1562 today. So it seems very likely the IQ going low at idle is kicking the fault. And again I didn't work on it, I got a migraine about 10 and pushed through until 3 but finally had to call it a day. I'm home now propped in the recliner watching the dogs be idiots. Tomorrow I will do the transmission dance with the MKII (an import RHD GTI of all things). Maybe Sunday I'll poke around my wagon if I feel up for it.