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Hi all!!

Been noticing more recently that when changing gear and going to accelerate the car is reluctant. It will initially start to pull below 2000rpm, but when it hits 2000rpm it just seems to stop acelerating, then slowly it gets up to 3000rpm and whoosh Turbo spins up and we're of like the preverbial of a shiny shovel!!

This can be a bit dangerous in certain situations, especially when I've got the 'van' on the back, climbing hills is fun when the car refuses to pull!!

The car is a 2001 2.0 110 HDi estate with 142,000 on the clock, regularly serviced, next one due soon.

Any help/suggestions greatly received!!

MTIA

M.

Sounds like you have to coax the thing by carefully balancing the throttle which would point to a vacuum problem in my mind.

You say this happens when changing gear or in other words when there has been and open/close action of the Turbo Wastegate. You could try swapping the Vacuum control solenoids on the bulkhead (swap them around) one controls the EGR and the other the Turbo.

Look also for vacuum line splits/leaks. The Vacuum pump itself on the end of the camshaft (rhs) has been known to crap out and not maintain enough Vac.

I'd start with the simplest things and go from there, ending perhaps in a visit to a Diesel specialist to check the vac pump etc. etc.

Throttle position sensors are also a favourite failure but usually flag the engine check light

Check also the intercooler and its hoses in case you're getting an air leak although to be fair you'd hear that as well.

See what the others say too........

I have noticed some times if I come completely of the throttle and then start again with only a small amount of throttle applied it picks up better than it was!! Hope this throws more light on my little problem!!

MTIA Again

M.

Air flow meter?

jasper5 wrote:Air flow meter?

Is there any way of testing this??

M

You could try disconnecting the wiring plug and see the reaction.

It may not be the Airflow Meter, but it sounds just like a fault I had on a Mercedes which turned out to be this.

The Airflow meter will not flag up the engine management warning light if faulty.

Welly wrote:Sounds like you have to coax the thing by carefully balancing the throttle which would point to a vacuum problem in my mind.

You say this happens when changing gear or in other words when there has been and open/close action of the Turbo Wastegate. You could try swapping the Vacuum control solenoids on the bulkhead (swap them around) one controls the EGR and the other the Turbo.

Look also for vacuum line splits/leaks. The Vacuum pump itself on the end of the camshaft (rhs) has been known to crap out and not maintain enough Vac.

I'd start with the simplest things and go from there, ending perhaps in a visit to a Diesel specialist to check the vac pump etc. etc.

Throttle position sensors are also a favourite failure but usually flag the engine check light

Check also the intercooler and its hoses in case you're getting an air leak although to be fair you'd hear that as well.

See what the others say too........

jasper5 wrote:You could try disconnecting the wiring plug and see the reaction.

It may not be the Airflow Meter, but it sounds just like a fault I had on a Mercedes which turned out to be this.

The Airflow meter will not flag up the engine management warning light if faulty.

I'll give it a whirl tomorrow....

Ta

M

Been out today so not had time to fiddle yet!! What I did notice was though, the problem is cetainly more obvious if you go WOT. If you change up and then gently apply the throttle it seems fine but if you give it some, WOT, it reacts as described flat spot 2-3000rpm then turbo kicks in..... If I back of from WOT then gently accelerate it behaves more normally?

MTIA

M.

Could be the air flow meter?

You could try *gently* cleaning the sensor(s) inside the unit but ultimately a replacement would be best. It's not something we normaly see on here to be fair but I know Supafrisk bought a new one from GSF for about £60.00 and reported a pleasant result. Don't run out and buy one just on my say-so anyway.

I seem to remember that the trottle pot and MAF share the same earth and early on in the days of D9's the dealers would separate these and replace with a better earth to prevent faults coming up all the time.

Well I've just come back from a test drive!!

I swapped over Wastegate and EGR solenoid thingies (Great techie speak, you wouldn't know I'm an aircraft techie would you??) and had the MAF of and give that a bit of a spray clean. Put it all back together ran it and listened for leaks etc. Couldn't hear any so went of up the road, wowsers what a difference!! Pulls like it never has!! gets up to red line so quickly now it surprised me!! to say I'm pleased is an understatement!!

Thanks to those for their suggestions!!

M.

WooHoo! nice one.

Cheap fix for the Win

(hope it lasts)

Nice result Glad you got it sorted.

Just had a nice result this afternoon, had a VW Golf TDI to look at, the breakdown service said broken driveshaft, as usual, I went with an open mind, jacked up the car, terrible noise on turning nearside wheel...took wheel off, took brake caliper off....out pops a nice round pebble from between the brake pad, brake back together, wheel on, 10 minutes time.
Customer asked for a bill, no charge I said, only a 10 minute job, remember me for your next service, certainly she said and gave me 20 quid.

jasper5 wrote:gave me 20 quid.

I'd have asked for £120.00




*runs*

Welly wrote:WooHoo! nice one.

Cheap fix for the Win

(hope it lasts)

Me to!!!

jasper5 wrote:Nice result Glad you got it sorted.

Just had a nice result this afternoon, had a VW Golf TDI to look at, the breakdown service said broken driveshaft, as usual, I went with an open mind, jacked up the car, terrible noise on turning nearside wheel...took wheel off, took brake caliper off....out pops a nice round pebble from between the brake pad, brake back together, wheel on, 10 minutes time.
Customer asked for a bill, no charge I said, only a 10 minute job, remember me for your next service, certainly she said and gave me 20 quid.

That is a nice result!!