Car Hiccuping

youthanasia · November 30, 2015

Hi All,

This is my first post on this forum, so hello everyone.

I purchased an IS220D last year and basically unknowingly broke it. I only drive in traffic on A roads every day. After reading the forums this is very bad for any diesel...

So you guessed it. Check VSC, EGR, DPF issues, the lot.

Had the car checked out and the DPF had completely failed. Instead of replacing, we did the gutting procedure documented on this site. After doing this the turbo kicked in later at 2000 instead of 1800. But all the lights on the dash are off and the emulator looks to be working fine. Great!

I stuck a piggyback ECU on the car and the car is running better than ever now. Just one issue, and it was very difficult to find, and really the piggyback ECU helped identify it.

If I put the car in second and rev to around 2800 constantly with the cruise control on, which is about 32 mph the car starts to what can only be explained as coughing or hiccuping... The rev needle will bounce sporadically 100 revs every few seconds. Sometimes it even seems to sort itself out and stop doing it! I took the piggyback ECU off and I was able to replicate the issue. So the new ECU is back on.

I've put some Wynn's all in one cleaner and I'm running that through now. And I'm thinking of doing an EGR bypass which is mentioned and looks fairly easy. Also I'm thinking of spraying some wynn's into the turbo air intake to see if that's the issue.

Anyone encountered anything like this. I've been looking around and not see much in the ways of what it could be. Could it be the DPF work?

I also read that if you gut the DPF you need to look at disabling the 5th injector??

Any help would be appreciated.

Thanks

Youth

steve2006 · November 30, 2015

Hello and welcome to the LOC.

I'm no diesel expert but the symptoms would suggest a fueling issue at the revs you mention which would suggest extra fuel is being injected for some reason at that point.

youthanasia · November 30, 2015

This would lead me to believe and issue with the 5th injector. As the purpose of this injector is to release extra fuel into the car to help clear the DPF. But there is no DPF now...

Think I'll reset the car and run the additives for now to see if it clears the blockage if there is one. I'll also give the EGR another polish this weekend.

Does anyone know of any good garages in the North Manchester area?

Might need one if I can't find the problem...

youthanasia · December 1, 2015

Think I may have found the problem, but still, time will tell.

Cleaned the EGR again, including the pipes and manifold. And obviously reset the car by disconnecting the Battery.

The car was running quite considerably better, after all this work.

I was doing some investigation into the turbo and noticed that in the air inlet manifold the open shut valve appeared to be sticking. A bit of lube and forcing it back and forth made the valve open and shut more easily.

Drove the car afterwards and no hiccuping at all, and very smooth delivery of power. Actually the car feels much better.

I'm going to do some more work on the turbo tomorrow to see if anything else is sticking etc...

Obviously I'm not waving a flag of victory just yet, but a run around town and I was nearly hitting 50 MPG. Well I'm getting 48-49. Great improvement whilst driving around at 30-40 MPH.

After all this I just need to drive to see if all is good.

zoran · December 26, 2015

Where exactly is this valve located? I've now got a similar problem with mine,.best described as hiccuping between 2 and 3000rpm

Everything else is clean and well serviced so turbo could be worth a look at?

zoran · December 30, 2015

Bump !

jackcramerr · January 1, 2016

zoran

Not sure what the original poster is referring to but my guess would be either of the following:

Throttle Body open shut plate/ valve. Very easy to clean and it might solve the issue.

Turbo waste gate valve ?

Other things I would look at in any car:

MAF sensor on intake

MAP sensor on Exhaust manifold

EGR as always

zoran · January 2, 2016

Hi,thanks I will try throttle body plate cleaning

All others MAF MAP EGR are all cleaned regularly

youthanasia · January 19, 2016

Hi Zoran,

Sorry about the delay, but no one responding to my original request. So I thought it was dead.

Buy the following;

Wynns Diesel EGR spray

Wynns Turbo Cleaner spray.

Open your bonnet and remove the left side and bottom plastics. You'll be able to get into the air-intake that way. Spray the two cans into the air-intake which is located at the front left if you're looking into the engine. The engine will speed up and make funny noises so be careful how much you spray at each time. Be patient is the key.

Buy some AR 6400 D and put this into the fuel tank.

Disconnect your Battery for a few hours and reconnect. Drive slowly for about 50 miles once you've reattached the Battery.

This will clean and free up any sticking parts.

Hopefully this will fix your car as it has done with mine. By the way. After 500 miles my car is driving better than ever. And also don't forget to clean the EGR if you have never done this.

Good luck.

Youth