1.7 dti (astra g estate) flat And hesitates until 2500rpm (turbo kicks in)

[jard]

Purchased a 2001 astra g 1.7 dti estate (103k miles) a week ago, never owned a diesel before and was told they are quite sluggish so viewing and test driving it I wasn't expecting nothing special.

But after using it now for a week before the turbo kicks in its very flat and hesitates.

After driving another example something's defiantly wrong, just not sure what it could be, I have disconnected the air flow meter which I was told it could be but there wasn't really any difference.

This is causing it quite dangerous to drive because I put away up a hill and it doesn't move, and when it does pick up I change up but then it goes flat again and there's nothing there, you have to drive it in the turbo all the time to drive normally

Any ideas guys?

[paul.spencer]

So I gather that there is no engine management light (EML) lit up on your dash?

If there was at least you might be able to get some fault codes to follow up on.

[jard]

No eml lights no, plugged into diagnostics and there was a few faults, but cleared them and plugging it back in tomorrow to see if they have came back.

Having a full service next week Inc fuel filter.

If I put my foot to the floor there's nothing for 5 seconds or so while the revs build (most times it kicks out smoke) then the turbo kicks in and pulls fine with no smoke, very strange

[paul.spencer]

guess maybe they were old codes. anyway let us know whether any new faults come up. I seem to remember reading a thread like this maybe on the Astra owners club forum. I'll let you know if I find anything like it...

[jard]

No codes are showing now after clearing them 48 hours ago.

Noticed today they it drives fine when it's cold with no smoke then hesitates roughly after a mile of driving with some black smoke when you hold your foot down (when it's flat)

I have just checked the turbo needle and is fine (just to check) but have been told it may be the egr?

[paul.spencer]

You would think that if there was an EGR problem, dirty or whatever, that you would get the EML showing and a P0400 fault code, but who knows? Why not remove the EGR valve, give it a jolly good clean with carb cleaner (some people then do a follow-up soak in petrol). See if it makes any difference at all.

Have you done all the basic maintenance stuff? Air filter, oil and oil filter, fuel filter - maybe throw some injector cleaner in the new fuel filter when you install it. See if that makes any difference if you haven't already done that stuff....

p.s. sorry just realized it says having a full service next week - might make a big difference. If not, then at least you will have ruled out those items.

[jard]

Had a full service today

Oil and filter
Pollen filter
Air filter
Fuel filter
Fuel addictive (injector cleaner)


Egr removed and cleaned, which was caked in soot and grime.


Needle wouldn't move but now moves freely, does run better but still hesitates to some degree




Engine ticks more now but sounds more healthy rather then deep a

[paul.spencer]

Thanks for the update. Always good to give a car a full service like that. No surpirise about the EGR valve they always are caked in oily/sooty crap.

When you say "needle" did you mean to say you got the EGR valve plunger bit moving freely?

Maybe its all good now, but could you tell us whether the original complaint - hesitation until 2500 rpm - has been sorted?

[jard]

yes, the plunger moves freely now.

i wouldnt say the hesitation is sorted but it has improved.

not sure what else could be the problem, but also heard that the cat can get bunged up and be a restriction.

[macker2b]

eat poo spammer!

[jard]

After hours of searching I found out about the fuel injector ecu (rear left of block) after taking a few bits off earlier to remove it I spotted a loose wire, when I reached for it I noticed it was a sensor, jumped back on the net to have a search and discovered it's the boost pressure sensor.

Just not sure where it goes :/

Had a look with a mirror etc but no clues, snowing which doesn't help

[paul.spencer]

hey I seem to remember a discussion about this - I think there was a sensor like what you are describing, a seperate barometric pressure sensor that fits into a bracket back there and sometimes comes off its bracket. I'll see if I can find the thread. Anyway its not the boost pressure sensor - just looks like it....

p.s. yeah, TIS shows an atmospheric prssure sensor that is supposed to slot into a bracket down low at back of engine, could email you a diagram if you want

[jard]

Sensor, boost pressure Opel Astra G Estate (F35_) 1.7 DTI 16V from Hella - 6PP 009 400-011

http://www.astraownersclub.com/vb/sh...d.php?t=209369

This is the sensor I have in front of me

[paul.spencer]

Well done finding the link to the AOC thread - that's exactly what I was talking about, the atmospheric pressure sensor isn't it? and looks the same as the boost pressure sensor mounted in the intake manifold doesn't it?

[jard]

Removed the edu, split the casing and checked the soldering which seems fine and cleaned the sensor I was previously talking about but still no change

I'm just courious because as first stated the car drivers perfectly for a few miles in the morning when it's cold but it's when it warms up it starts hesitating performance wise

So racking my brain to think what would change regarding to the temperature the cars at?

[jard]

After even more researching and being curious why the edu connector is wet with diesel, let me onto checking the ecu (top of engine) connectors to find yet are wet with diesel also..

Leading me onto think it's the fuel pump solenoid at fault..

[paul.spencer]

Removed the edu, split the casing and checked the soldering which seems fine and cleaned the sensor I was previously talking about but still no change

I'm just courious because as first stated the car drivers perfectly for a few miles in the morning when it's cold but it's when it warms up it starts hesitating performance wise

So racking my brain to think what would change regarding to the temperature the cars at?

regarding unexplained (no fault code) performance issue when the engine warms up, it has been fairly well documented that the crankshaft sensor can cause issues when warmed but not when cold. It causes some running issues without leaving any fault code. Seems crazy to replace some component like that only hoping it might help, but I gather it has done the trick for lots of people. I guess if you could get your hands on a spare crankshaft sensor you could try it and see if it makes a difference

After even more researching and being curious why the edu connector is wet with diesel, let me onto checking the ecu (top of engine) connectors to find yet are wet with diesel also..

Leading me onto think it's the fuel pump solenoid at fault..

I re-read the thread and think this is the first mention of diesel in the EDU. As you may have found out it is a common problem. Peeople have managed to replace the timing solenoid, or have done repair jobs using epoxy around the wires, and often people install a connector block to stop the flow of diesel ino the EDU.

[Heley]

When mine was a 1.7DTI, i had an issue with it when it went real sluggish with no fault codes. Turned out to be the airflow meter. Might be worth borrowing another to try?