! Desperated situation Engine stutter on acceleration :(

[gjenck]

Hi

I'm first time posting here , as i had to ask you guys maybe can help me in this situation .

First of all i have Octavia vRS 1.8 20v 2002 (AUQ).

I was searching and examining many threads on the net about my problem but it was yet unsucessfull , the problem not discovered.

The problem consist maybe more then one part failure as i found one of them was the pcv hoses leaked.

So start with the problem:

-When i was bought the car i readed the obd eroor codes and i found an eroor which i still have this days , pressure drop between turbo and throttle valve check dv (i think is 17705) , the car was working well besides the error.

-My car starts to hasistate , stutter on acceleration ,once-twice a week before 1 years ago , much more i noticed that in could morning after starting the engine the engine sometimes was stutter very hard and stalled , if i started again mostly the problem dissapeared and the car went well.

-time after time the car was stutter on acceleration more and more freqwently and have no power as before,as now after aprox 1.1/2 year the car almost hasitating hard on acceleration , eats a lot, stutter on acceleration even in neutral gear , when i change gear the engine is stutter once hard as wasnt before , the if i keep accelerating the car is hasitating stuttering .

- Strange because usually i never get any check engine light on my dasboard , the error appearing if i reading from the ecu !

- Once when the car was stutter on acceleration i was forcing to accelerate almost 2 minutes long and then i got once a blinking checkengine light on my dashboard !!! ...i readed the codes and i found another problems P0302 Cylinder 2 Misfire Detected ,P0303 Cylinder 3 Misfire Detected ,P0301 Cylinder 1 Misfire Detected ,P0300 Random/Multiple Cylinder Misfire Detected .

I cleared the error codes and never comes back.

-So couple of monts ago i was reading somewhere that could be a cracked pcv hose ... as i felt bad smell while i was staying at red lights i started to search for the crack,. I found that the S shaped PCV hose which comming from the T-piece valve (PCV Valve) up to the Y hose ,was cracked on both ends , so i changed . The bad smell dissapeared , the car was working the same no improvement.

-Then after 2 month it started to felt the smell again , (meanwhile the car was stutter on acceleration more and more freqvently ) i was searching again ,for cracks , i fund now that the L shaped hose from the left side of T piece to the engine block was cracked ... so i changed and i removed some of the valves to test like dv ,n249 ,n112 , was working well in my opinion.

So after this hose change the smell dissapeared again , but the engine have no power and still stutter :(:(:(

- I was checking by eye the route from air intake to throttle valve , i cant find any visible crack.

-Strange now in december started to stall almost every morning at first second starts !!

-If i just slightly press 15-20% of throttle the car slowly pulling without noticable stutter hasitation.

I saw somewhere a crack test with air pressure , maybe you guy suggest to try first the cracks.

In my opinion can be laso the Egr valve , or The N75 ...? i will check/clean somehow

So i really need some suggestion , i\m really desperated as i have the problem from 1 half years ago , and now the car is almost stutter at hard acceleration.

-(The Spark Plugs was changed with no effect :()

I was also thinking on many variation , could be the Turbo too ? or the dv /egr ...strange because if i push the acceleration the car starts to pull then rapidly stalling back alot then sometimes pulling again hard , so a kind of stutter.

When is stalling back its like when maybe the turbo boost is diverted elsewhere and the engine dies back like when you OUT OF FUEL .

Maybe should i start to check the fuel filter too , or somehow the fuel pump ???

...

many reason ...

Ok thanx in advance ...i apreciate everyone suggestion or question ....or here or at [email protected]

Bye

[chicken_eyebrow]

Have you tried replacing the coil packs? It does sound like a coil pack problem to me, especially with the misfires you mention.

If you have a Skoda dealer near you (I'm assuming you're not in the UK?) they should replace the coil packs free of charge if they haven't been changed before. See this thread:

http://www.briskoda.net/forums/topic/193376-audi-coilpack-recall-turned-into-official-skoda-recall/page__st__420

[gjenck]

Yess , i was wonder also could it be , just strange is that it comes this error once when i was keppeing acceleration about 1 min and was heavy stutter , so the ecu could missunderstood and gave this missfire error.

Anyway thanx and it is another possible fault , i will count with this too .

Thanx again .

Other suggestions still are wellcome

[sav26]

i would agree the first port of call would be coil packs i had a similar problem but only on one cylinder cylinder 1 which caused no power very jerky turned out to be the coil pack on cylinder 1 changed that and she was sweet again but why did u leave it that long after knowing u had a problem would have been one of the first things i would have done was get it diagnosed properly at a garage then have the work done even if u did it yourself but i wouldnt leave it it will only get worse but does sound like a coil pack issue from the problems i had i also have a 2002 octy vrs

[gjenck]

Of course i was to diagnose at first , just at that time the car was working well 1 , then started to stutter rarely, the problem was that in my city there is no Skoda/VW Service , and the others they could not tell which part is bad from the diagnosed ' pressure drop between turbo and throttle valve check dv' so i have no money to buy parts after parts to guess which it was

The better way is that i can take parts for testing from another RS , maybe i will as i have somebody who have also RS.

Thanx for reply i will check somehow ..

Im not soo good in english so please tell me exactly what you understood under coil packs ? the coil on the top of each sparkplug ??

THX

[chicken_eyebrow]

Yes they are the box shaped things on top of each spark plug.

[Longyear]

Be REALLY careful pulling the Coil Packs off the Spark Plugs, especially if you don't have the proper removal tool........ It's possible for the Coils to snap, half way down the shaft (where they are glued).... this leaves half of the shaft sitting on the spark plug and it's very hard to then access and remove!

............ I learned this the hard way!

Edited 8 May, 2012 by Longyear

[za_killer]

coils are never glued. they are secured down by vacuum...

[Longyear]

coils are never glued. they are secured down by vacuum...

I'm not talking about the coil being glued onto the spark plug lol! .... yeah, I see (and feel) that vacuum..... but I don't know if you've ever have a coil pack snap in half on you, but the top section of the (admittedly crappy) ones I have here from the local auto parts place, is glued onto the bottom shaft.

As I say these are 'veng' crap, not VAGs so perhaps there is no glue on OE ones, but there are on these, and probably the crap that's sold on eBay.

Edited 8 May, 2012 by Longyear

[marko pollo]

It might be the MAF senson??

My MAF is shagged and i have a similar prob.

Might be worth a look??

Marko

[Chris Coates]

Have a quick look on Scribd for the workshop manual if you've not got access to Haynes(and probably even if you have) - it may help you diagnose things a bit better, and at least give you an idea of what is next in the airflow/fuel/exhaust circuit...

...For instance on a TDI - a dodgy 109 relay would cause similar cut-out/stuttering symptoms. An improved design 109 relay was released to fix it....

Not entirely sure about the petrol VRS's but I would assume if you can't see any air loss in the system... Could be anything from a vacuum pipe to a sticking turbo to dodgy sensors along the way.

If you're sure it's not the turbo or the pipework... Start at the lowest possible denominators for the electrical system and work your way up.

[skudman]

Right this all sounds way too familiar at the moment. Id hate to step on anybodys toes but.....

The vrs doesn't monitor fuel line pressure. The main symptoms that cause multiple misfires are down to fuel line pressure and not coil packs failing. First check the hose from inlet manifold to regulator. If that's ok remove the regulator and make sure there is no debris in the receptical for it in the end of the fuel rail. I replaced mine with a new unit (about 40 quid for bosch replacement). That cured the hesitation. As for 17705 fault clean the throttle body before anything else.

Then start checking hoses starting with vacuum from inlet manifold.

[Chris Coates]

Right this all sounds way too familiar at the moment. Id hate to step on anybodys toes but.....

The vrs doesn't monitor fuel line pressure. The main symptoms that cause multiple misfires are down to fuel line pressure and not coil packs failing. First check the hose from inlet manifold to regulator. If that's ok remove the regulator and make sure there is no debris in the receptical for it in the end of the fuel rail. I replaced mine with a new unit (about 40 quid for bosch replacement). That cured the hesitation. As for 17705 fault clean the throttle body before anything else.

Then start checking hoses starting with vacuum from inlet manifold.

Yep - +1 to that.

A lot of issues with cars in general are usually caused because the lowest common denominators fail (usually because they're made to tender by the lowest bidder) making more expensive things fail down the line.

Start with the basics - make sure fuel is getting to the engine, make sure no vacuum pipes/airflow pipes are leaking, make sure oil is getting where it needs to - namely turbo, make sure electrical components are all working.

Past that point is usually where something more serious is at play. But until then, i'd take the workshop manual and step through each component bit-by-bit and track it down.

[mdon]

I used to have this problem on my 1.8 20v non-turbo and all it was was gunk on the butterfly in the throttle body, try getting a aresol of carb cleaner (about £3) and cleaning it with that, it sorted mine and its always worth trying the cheap solutions first.

[gjenck]

Thanx for advices

Yess .

As many of you suggested i will try to get part by part , starting from fuel flow to fpr ,to the vacum /boost system leak !

Yesterday i was examining a lot the whole system and now i'm a lot more clear about how the whole stuffs is working and what relations have with each other.

As i mentioned i always have fallback after gearchange in power , i noticed after examining the system that can be possible that Or the DV not opening (maybe the vacum controlled hose) or the wastgate actuator (pressure unit) ...so can be ...

I noticed from schemes that under acceleration the N249 can control the boost to reach also the DV !!! As i know the DV can open controleed by both vacuum and boost ...am i right ?? If so can be that somehow the N249 under acceleration opening and let the DV opens and in that case the turbo boost will be diverted back in front of turbo (TIP).

This tought it sounds strange because just electronically can control the N249 so maybe i'm wrong...

I check the schemes and i will make a checklist for better start of error search.

Yesterday I was testing the N75 and its working well.

[chicken_eyebrow]

Yes the N249 can open the DV if it needs to. normally theres a vacuum feed from the inlet manifold which starts pulling the piston up on the DV when you close the throttle, and the prssure of the trapped boost pushes it up even more so the boost can escape.

If there's a problem with the wastegate actuator though the ECU can tell the N249 to give the DV a vacuum while the turbo is boosting, that way the DV opens at part boost and your boost escapes.

I still think the coilpacks are worth checking out as with the current recall they are FREE to replace by a dealer. If you have VAG-Com you can do some logging of block 032 to see whether it is underfuelling.

[za_killer]

N249 controls the DV and you can bypass it (search the forum for guides and pics). this should prove the n249 functional or faulty.

dunno if you checked yet, but i would start with the DV, and see if it's membrane is still intact

[gjenck]

My frend have wag com , several type and the he got just always the 17705 pressure drop error,

I have the ELM 327 bluetooth adapter with android phone (torque program) i know that is not the best but it is logging many things , so maybe can you help me if you know what to log with ?

And what exactly mean under logging of block 032 ????

Strange thing is that i never saw (read) with my elm327 the 17705 error (as my frend could with the wag com) but as i know my frend never could log/read the turbo boost but i can see with my elm327 ...! strange

Once i got error with my elm327 when i was kepping acceleration about 1 min. under engine hasitation and then it apears the blinking checklight on the dash also i read the cylinder misfire error with my elm327.

The misfire error never apeared again .

Yess i checked manually the n249, n112 with 12 volts and was working , also i checked the DV i aplied vacum and was opening , i'm forget to check if it works with pressure instead of vacum. maybe should i start to check again the vacum hoses !!

Edited 9 May, 2012 by gjenck

[gjenck]

How can i know if my coilpack was changed already or not , maybe thay can ask Skoda at a skoda service nearest to me ?

[gjenck]

OPS

i tought on something ,!! Maybe the car can control and opens the DV under BOOST too with N249 using when ASR to get back the power to maintain the wheels antispin !! ? ?

Question build Questions

[chicken_eyebrow]

Yeah it can open the DV under boost so bypassing it is one way of ruling it out as being the problem.

Block 032 is something you can log with VAG-Com but probably not with Torque. Your friend with VAG-Com might be able to do it for you?

If you check your car in to your nearest Skoda dealer and tell them you want your car checked under Recall number "28F7" they should look at it for you and then if you have any of the older type coilpacks they will replace them free of charge with the latest ones.

[skudman]

Clean your throttle body first. Soon as the 17705 fault is stored the ecu won't allow boost anyway. This caused me to Chase the wrong items for ages.

Ive been chasing my tail on a number of issues and codes and all of them were due to cleaning throttle body, fpr, and broken wires to n75. Skoda seem to have used thinner wires to the other vag models

[gjenck]

Anyway that is a good ideea to clean throttle body +puel pressure regulator before going further ...

Also checking the fuel pressure manually and with Wag

....

[skudman]

I don't have vag.com as previous attempts have failed to allow me to run it. I have a 25 pound Fcr from eBay, and run Android torque to watch live data. After the rs was in the dealership two days last week with no fault found plugged in all that time on the actual equipment for them to suggest they couldn't find a fault despite me suggesting fpr I have no real faith in deep delving diags anymore.

[gjenck]

I don't have vag.com as previous attempts have failed to allow me to run it. I have a 25 pound Fcr from eBay, and run Android torque to watch live data. After the rs was in the dealership two days last week with no fault found plugged in all that time on the actual equipment for them to suggest they couldn't find a fault despite me suggesting fpr I have no real faith in deep delving diags anymore.

Yess it can be that the wag diag not telling anything about because there is no sensors for every part of the car to get feedback of whats happening .

I use also android torque , just i'm not involved yet deep , maybe is there usefull realtime informations in it.

What do you have turned on to log in torque ?

The refresh of data's/ gauges are the same slow (1, 1.5 sec fps) ?

Will be good if you can give me your turbo boost data to compare with mine. or a better way to send me the logfile from sdcard\torque\triplogs

Edited 9 May, 2012 by gjenck