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Discussion Starter · #1 ·
Hello

I have a PD115 and although I know the full power is not present until above 2k rpm in each gear my car has started feeling very lumpy below 200 revs, but still has almost the same power above that! It's still drivable and it has not caused an engine check light yet but I'm quite concerned.

Has anyone had this type of problem before and does anyone near junction six of the M40 have Vag-Com to do some checks with me??

Many thanks in advance
 

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Hi, I drive a 115 bora and used to have hesitation problems when i lifted off just above 2000 rpm. This had been made worse after the remap.

From what i can gather the engine will be a lot happier after Ive done the panel filter and ducting mod so as it can breathe properly.

I'll let you know the results, as my car didnt show anything in VAG COM at all.

Mart
 

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Discussion Starter · #3 ·
Bump..

Hum, am having real difficulties shifting this problem, the car still feels like it regains full power once it's been in gear for a few seconds and once it's above 2k rpm

During this week I have tweaked a few things in attempt to fix this, I found that the solenoid for the anti-shudder valve had snapped off and melted on the manifold to EGR valve pipe, so I promptly replaced this along with the vac lines that felt a little perished. Lastly I disconnected, cleaned, lubed and refitted the connector to my oil temperature / level sensor since this had previously generated the fault: intermittant / implausable signal through Vag-Com.

Now that these have been fixed do I need to do some sort of reset with Vag-Com so it doesn't try to compensate for the bits that were at fault above?? I hope to get in touch with a friend to get this done soon.

Lastly, the vent holes on my EGR valve are weeping oily stuff, the car is reaching boost which I can tell through my boost gauge but this pressure loss through the holes could be causing the hesitation / bucking when I try to floor it.

http://forums.tdiclub.com/showflat.php?Cat=0&Number=996133&page=&fpart=all&vc=1

The link above has a picture that shows where my leak is coming from, except my picture would have no silver parts in, just black oily stuff coating the lot.

What have I done... Any pointers would be truely appreciated. J'mee
 

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I also have a bora 115tdi and also suffers from the same problem (Changed maf 3 times and still no Power below 2000rpm), this makes city driving horrible and very slugish.

Ive seen this problem related in many forums and the solution is somehow conected to cleaning the intake and egr and maybe the temperature sensor.

I will try both then post results.

Can we see the temperature sensor values in climatronic (not vag com )

Thanks in advance
 

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Discussion Starter · #5 ·
Excellent! Was worried that my thread was not being read enough, so many thanks for your comments!

Since my last post I have cleaned up the EGR valve has best I can but it doesn't seal very smoothly which could cause this hesitation since it is unmetered air-flow. Cleaning it hasn't fixed it so maybe the diaphram in it is now torn. I don't fancy replacing that so over the next few days I will be replacing the oil level / temperature sensor ( ?65! ) because that was throwing an itermittant implausable signal, still.

Will update you all, hopefully with good news in a few days.
 

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I have a PD115, But, I may not be able to help you as I have never had this problem. BUT this may be because I (almost instantly) changed the MAF to a PD130 one, I have a Green cotton panel filter and have a different N7J valve. I find my power is much smoother and comes in earlier at around 1500 revs. 
 

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Well it may be the temperature sensor, i have read that it can be the cause of flat spots and hesitation.
 

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I conected vag com to my car :

Error :

Coolant temperature sensor -Open or short to ground - Intermitent

I cleared this error and went for a spin, conected agin and this time no errors.

Can this cause my missfire ?

My car doesnt do any smoke, but sometimes it smells really bad, like bad combustion...

If the ecu is overfueling how come there is no smoke coming from the exaust ???
 

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Discussion Starter · #11 ·
Zero good news to report, have now changed the ?60 oil temperature / level sensor and resolved that fault code, but this has not cured the hesitation!

Apologies for giving this information in dribs and drabs but I am now running a fuel cooler, which works great but maybe the extra fuel I have been able to get in to the injectors has clogged the fuel filter enough to cause hesitation when trying to accelerate. Having said that it consistently stutters only when trying to accelerate hard below 2000 rpm.

I'm really stuck now, any pointers would be really appreciated.
 

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My problem is diferent from yours, but its intermitent for now car is running fine, but i know its going to happen again....

The only error is the coolant temperature sensor, errased but comes back after a day or two, im going to clean the egr and the intake.
 

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Discussion Starter · #13 ·
Bump!

Had my EGR adaptation and setting reset this evening by a friend in the know, and now my problem is greatly reduced so I think all that is left to do is to replace my old and tired EGR valve.

Was told that sometimes the EGR valve requires resetting and for it to be retaught how open and close it is because the spring in the looses strength as it gets older and the slow clogging and occasional cleaning of it can throw out the settings it's learnt.

I hope this may be of some help to others.
 

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Mine is doing the same thing and have the shareware version of vag com so i cant change the adaptation values...

My car suffers from hesitation on aceleration, boost fluctuation and poor Mpg
 

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re the EGR    either get a new one or convert it to a Wingnut stealth pipe,  look on Fred's for info,  as to the other problem (if you still have it)   I would check for full stroke of the turbo vanes/  the vac pipe to it and the controll valve for operation and or dirt.  I sounds as if the egr and complete inlet manifold need a good clean out,  removal neccessary,  best of luck 
 

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Discussion Starter · #17 ·
Hiya, little progress on this issue I'm afraid, have tried disconnecting the EGR and temporaily blocking it off completely but the fault is still there. Maybe this is specific to the PD115 where the ECU cuts the fuel is the boost is too high below 2k revs. I notice on my boost gauge that the boost gets up to just over one bar very quickly, even when pulling away at low revs and the chugging hesitation doesn't match the timing of the boost cutting back when it starts to happen.

My turbo isn't broken, almost zero play in the spindle and it doesn't smoke plus it holds the correct boost all the time in every gear, above 2k revs. Maybe the actuator is getting a little softer following all the low revs action I've been giving it, this part cannot be purchased on it's own from VW much to my dissapointment so maybe a specialist company like Allard could supply a new one. As you can image this is a bit of a big if and I don't fancy spending out on this replacement if it doesn't fix it. To be fair the N75 and ECU can measure and adjust quick enough so it should just be able to make the boost on slower but when freer flowing exhausts and de-cats happen on these cars the backpressure is greatly reduced on the turbo.

I had a go at removing the c-clip on the actuator rod yesterday so that I could extend the rod by one turn to see if it gives the N75 a bit more control on the boost that likes to come on so quickly and agressively. I couldn't remove the c-clip though! Maybe there's a better tool for it, was sure I'd be able to remove it with the flat-headed screwdriver though! If anyone else fancies trying this out please let us know the outcome, in the mean time I'll try and get another pair of hands on the case to adjust mine.
 

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Discussion Starter · #19 ·
Hiya

Yes I have a spare N75 valve to swap out for this test a little while ago because I run one from a PD130 at the moment to go with the PD130 MAF, but that hasn't cured it.

Please read again what I was proposing to do to the actuator rod, someone please correct me if I'm wrong because I don't want a blown tubro but extending the rod should slow down the speed the turbo spools up and shortening it usually makes it boost up so quickly that it overboosts.

Another port of call I will consider is contacting PD turners regarding this since it may be something that can be electronically adjusted so that the ECU doesn't mind the boost coming on so early. Signs of the actuator getting softer with age maybe??

Thanks for your comments anyways
 

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Any improvment Blackseed ?

My guess is that my problem is really with the egr valve, i think it sticks in the open position.

I already replaced the Maf, N18,had turbo rebuilt, cleaned the egr and intake, checked injectors and still have lack of power/stuttering at low rpm.

My only chance is to block the egr or buy a new one, but they are quite expensive...
 
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