Check Engine Light: 17964 Charge Pressure Control

J

jasonngan

Member
Joined
Feb 22, 2005
Location
a
TDI
jetta, 2002, silver
Hi All,
I am a newbie to TDIclub. Thanks for all your posts and help in the past and they have been helpful.
I have a 2002 Jetta TDI without any modification so far.
Last week, my car had an engine light on and I used vag-com 311.2 and found out that it got "17964 - Charge Pressure Control: Negative Deviation / P1556 - 35-10 - - - Intermittent".
I cleaned up the intake manifold and also the EGR value, but there's almost no change. I vag-comed my car again and find the MAF value to be 430mg/h, which is higher than the typical value. The specified/actual MAP values seem to be much lower than their corresponding typical ranges. The specified MAP can sometimes reach the typical range while the actual MAP is always lower and about 1200.
The EGR duty cycle (D. Cycle) starts with 4.8% but it changes to a value within typical range.
Does anyone know what's going on? By the way, I am wondering how I can check the vac hoses effectively? No auto shops are willing to check the vac hoses for me so far (autozone/firestone).
I also unpluged the MAF sensor this morning for a 2-mile trip and found no change. I actually changed my MAF sensor/ air/oil/fuel filter 3 weeks ago and I don't think I did anything wrong.
I also put 1/3 of seafoam in the fuel tank, 1/3 in Intake manifold and 1/3 into the motor oil 2 days ago. I saw some smoke but no significant change so far.
The check engine light has been on but it might be off 20% of the time. Is it safe for me and the car if I keep making short trips while this problem has not been resolved?

Thanks for all your time and effort helping me!!!

Jason
 
J

jasonngan

Member
Joined
Feb 22, 2005
Location
a
TDI
jetta, 2002, silver
I saw your info. Are you still getting 55ish mpg gas mileage right now?
 
MileageDude

MileageDude

Veteran Member
Joined
Mar 3, 2003
Re: Check Engine Light: 17964 Charge Pressure Cont

Take a hose either one you find around the parts store, or the one that is the original off the EGR valve. Connect to the top of the EGR valve. Suck with your mouth/lips on the vacuum hose. If you have resistance and the valve seems to have sealed vacuum it ain't your EGR Valve. But if you suck on the hose and the EGR valve has no back pressure/vacuum ...then it's your EGR valve. The EGR valve goes often. It will throw that exact code. You lose power in the 2,500 to 4,800 rpms ...and you also smoke.

So the deal is, ....get a vacuum hose, connect it to the top of the inlet of the EGR Valve and suck on it. If there is no vacuum/suction from sucking on the other end of that open side of that hose ...you're problem is an EGR Valve.

M.D.
 
J

jasonngan

Member
Joined
Feb 22, 2005
Location
a
TDI
jetta, 2002, silver
Re: Check Engine Light: 17964 Charge Pressure Cont

Thanks a lot, M.D. I will try it out tomorrow morning and find out. Thanks!
 
J

jasonngan

Member
Joined
Feb 22, 2005
Location
a
TDI
jetta, 2002, silver
Re: Check Engine Light: 17964 Charge Pressure Cont

It seems that there's great resistance after sucking on that valve for little bit. Does that mean the problem is not from the EGR valve. What else would you suggest me to check? Thanks a lot!

Jason
 
MileageDude

MileageDude

Veteran Member
Joined
Mar 3, 2003
Re: Check Engine Light: 17964 Charge Pressure Cont

A couple of items come to mind. You may have vacuum pressure with a fresh hose sucking on the end while connected to the EGR Valave ...but you may have worn out vacuum hoses within the engine system "due to age." Usually you replace all vacuum hoses every 2-3 years depending on mileage. There are people here on the board that sell complete vacuum hose kits ready to install for about $50. Don't buy at the dealer because they charge by the foot and it runs around $7 - $10 a foot.

Lastly, it could be your MAF SENSOR, best bet is to find a member who lives close to you and switch out MAF sensors to see if it's that or not. Try doing a GTG in your area or looking for one close by. Well worth the effort and time.

There are other possiblities, all stem from minor to costly. One thing is ...you could have a clogged snow screen on the air intake. You could have a failed relay vacuum switch ...I forget the name of it but there are 2 on the firewall where everything connects, and one can be interchanged with the other to test for failure. Another is ...clogged turbo vanes, the VNT vanes could be ...carbon'd up and not... free to expand under demand.

You could have a gasket leak on the EGR connection, or the cooler pipe of alumimum could be cracked and leaking...

I will search some more on the obvious which was put forth on these boards over the past 4 years and see what links I can post.

M.D.
 
J

jasonngan

Member
Joined
Feb 22, 2005
Location
a
TDI
jetta, 2002, silver
Re: Check Engine Light: 17964 Charge Pressure Cont

Thanks so much for your time and effort, M.D.! What's GTG actually? Your suggestion is great and I will try to check out every single one of them.

By the way, is there anyone living in the St Louis who is willing to help? Does any reader here have vacuum hoses kit for sale? Your response is highly appreciated!
 
Y

ymz

Top Post Dawg
Joined
May 12, 2003
Location
Between Toronto & Montreal
TDI
2003 Jetta TDI Wagon, 2003 Jetta TDI Wagon
Re: Check Engine Light: 17964 Charge Pressure Cont

GTG = GetToGether - at various times, TDI owners/mechanics/tinkerers/suppliers get together for a day of repairs, advice, TDI-talk, food, beer, etc...

If you'd like a TDI specialist shop to look at your car, look up www.oilhammer.com - one of our Timing Belt gurus... in Union.

Good luck,

Yuri.
 
F

fhryder

Veteran Member
Joined
May 21, 2003
Location
New Brunswick, CANADA
TDI
Golf GLS TDI (tornado red)
Hi:

I've got the same symptom 17964 etc
and a pronounced lack of boost.
also a check engine light occasionally.

Using vagscope on channel 3 I found that the MAF specified was not matched by the MAF actual.

Checked the vnt mechanism and found that it was stuck in the down position (I think that's low boost). If you check my posts of a couple of years ago when I got the car it was stuck solid, took a couple of weeks to free it with lots of soaking in wd40 and moving up and down with a wrench. Looks like I've got to give it another treatment.

Gave it the treatment, now MAF actual is about 3/4 of specified,
boost feels like it's back and it's not throwing codes any more. So we'll give it lots of exercise in the next few days, and I'll look for leaks around the intercooler, seems to be some oily crud on everything.

Frank
 
J

jasonngan

Member
Joined
Feb 22, 2005
Location
a
TDI
jetta, 2002, silver
Re: Check Engine Light: 17964 Charge Pressure Cont

I finally get it to accelerate up to about 85+mph. Is it normal? I remember I should be able to get up to 90mph in the past.
I found a piece of paper on the snow screen and I was shocked. That looks like some label originally sticked on a part. Even so, I am glad that I did clean up the intake manifold. I am still interested in improving the car's performance.
M.D. Thank you very much for helping me sort out the problems.
By the way, in the thread <a href="http://forums.tdiclub.com/showflat.php?Cat=&Board=UBB17&Number=1063020">turbo problems solved</a>, the original writer, Gelly, mentioned that his car got "turbo pressure". Is it same as 17964?. Do you think I should do the same to increase the gas mileage? My 2002 Jetta got 120K and I don't think the former owner will do this kind of work unless it is necessary. My car's gas mileage before the error 17964 happens is only about 27mpg since I bought it(half year so far). I am very interested in find out the problems.
Thanks M.D. again!!!
 
R

rdkern

Top Post Dawg
Joined
May 21, 2004
Location
Humboldt Co CA
TDI
Passat 1997 silver (sold after 11 years), Jetta 2000 atlantic blue
Re: Check Engine Light: 17964 Charge Pressure Cont

My 97 Passat gets to 90 before I'm aware I should life my foot. If you're having problems getting to 85, something is wrong, imho.
 
J

jasonngan

Member
Joined
Feb 22, 2005
Location
a
TDI
jetta, 2002, silver
Re: Check Engine Light: 17964 Charge Pressure Cont

sign... My car finally got the engine light again even though it has been running much smoother than first. I guess I will clean up the check valve to see if it got stuck and then VNT and replace vacuum hoses. Any suggestions other than these?
 
J

jasonngan

Member
Joined
Feb 22, 2005
Location
a
TDI
jetta, 2002, silver
Re: Check Engine Light: 17964 Charge Pressure Cont

I vag-commed my 02 jetta again and found that the actual MAP value is always lower than the specified MAP value for about 100mbar when rpm is increasing. The actual MAP value will match the specified MAP only when the rpm is relatively low. Does anyone know what's going on? Thanks!

Jason
 
You must log in or register to reply here.
Top