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Cdti lack of power

Whiteakita

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Location
Bishop auckland
Car
2009 accord idtec
Hi everyone, I have recently bought a 2004 accord cdti.
It has a very low power problem.
In 1st gear there seems to be no turbo boost at all, 2nd gear boosts at 3500rpm,3rd gear boosts at 3000rpm,4th gear boosts at 2500rpm and so on.
So far I have cleaned the egr valve and throttle body, tested egr valve and the piston opened with 12v applied, cleaned maf and map sensors, it's fully serviced including Bosch fuel filter, used vacuum on the turbo actuator and it moves easily also lubricated it.
I removed the egr pipe at the front of the engine, it was clean, went for a short drive with the pipe removed and the car was a lot better in power off the turbo, first gear was almost normal and was no longer dangerously underpowered when pulling away from a standstill.
The car with the pipe removed revs freely as it should, once the pipe is connected again the revs are a lot slower to rise.
I'm thinking it's really struggling for air.
Has anyone on here have any advice as to what the problem could be ?
It's like the manifold is severely blocked up but it shouldn't be as everything else connected to it was quite clean.
 
Hi Whiteakita,

First of all congrats on buying the lovely Accord.

Secondly sorry to hear u r experiencing this issue.
By the sound of it, seems like you need to blank off the egr and get the car remapped.

Hopefully one of the experts (F6HAD) on these cars will reply very soon.

Hope your issue is resolved very soon.
 
If the EGR valve has been tested by applying 12v to open it (and, most importantly of all, it closes fully without delay when the 12v is removed) then blanking it would be unnecessary. Otherwise the symptoms do suggest an EGR valve failing to close.

The bit about removing the EGR pipe to improve running confuses me, however this doesn't really suggest a blocked intake manifold as the air would still need to pass this way whether the EGR pipe was connected or not. But this might indicate a blockage in the boost pipework, possibly even the air filter? I hope it isn't a faulty turbo.
 
Looks like I will have to use my phone.
The air filter is brand new.
The pipe is the one that feeds into the front of the inlet manifold, there's definitely a restriction somewhere.
I was thinking turbo but how would a turbo make the car rev slowly at a standstill ?
With the pipe removed it revs much better but still not 100% I don't think.

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Might be worth trying - Unplug your maf sensor and go for a drive. If it cures all the symptoms that's your culprit, I had a similar situation with an old car.

Just a word of caution: I haven't done the research for this specific car but it'll probably throw an EML and I know you mentioned you cleaned your maf which is why it might be worth checking, they're very easily damaged and will give symptoms similar to what you've explained.

I would of thought if it was the turbo or EGR you'd get a code spat out if there was insufficient boost pressure.


Sorry if this is no help.
 
I forgot to mention I did try unplugging the maf but it was much worse and wouldn't rev over 2000rpm.

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It did have P1237 fault code on the car and the glow plug light flashing when I got it. I scanned it for the codes then cleared the codes, i haven't rechecked today but the glow light is no longer flashing.

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Once the turbo kicks in the car goes like hell!
The only thing I can think is the inlet manifold is very badly blocked, the car has done 188k miles.

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I'm pretty sure it's a leaking egr. I solve these on a regular basis. Drop me a line for pricing and options for diagnostics and a permanent fix.
 
Where do you fit the egr blanking plate on these ? Is it on the pipe coming out the egr cooler ?


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I have had another look at the car today and noticed the revs are very slow to react between 1k and 2k rpm, after 2k rpm it revs freely , would that be a symptom of a failing egr valve ?
I think if it revved properly it would be a lot better.

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I have sprayed some intake cleaner into the manifold today with the engine running but it's made no difference.

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If I go ahead and fit the blank plate will the car go straight into limp mode without remapping it immediately?
Or can I fit the blank plate and the car will run ok ???
I'm not bothered one bit about a light being on the dashboard, I just need the car running right.

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Blanking the EGR valve without the necessary map modifications will result in the vehicle going into limp mode and having a 2000 RPM rev limit. However - ***uming your problem IS the EGR valve not closing properly - the engine should pull like a train up to that rev limit, thereby proving that the valve is the problem.

But you described how you already tested the EGR valve by applying 12v and watching it open. I did previously ask if you also checked that is closed fully without delay, but you didn't reply...
 
Yes I checked the egr valve with a 12v feed, the large valve looking rod inside very quickly opened when 12v was applied and snapped shut when I took the 12v feed away.
I did say this in one of my previous posts.
Whatever the fault is it makes my car rev slowly between 1 and 2krpm then after 2krpm it revs freely as it should.

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Whiteakita said:
I did say this in one of my previous posts.
Can't see where, so must have been one of those posts that came out blank then. But anyway, if you really are sure that the EGR valve is closing then obviously there's no point in blanking it off.

Getting the car hooked up to interactive diagnostics (certainly HDS) would be a good move. I'm not convinced that this is a blocked intake manifold, especially as it runs a lot better with the EGR pipe disconnected... which still makes me wonder if there's a blockage somewhere earlier in the intake system (you ruled out the air filter, but what about the intercooler or boost pipework?)

Has it ever been remapped? That can sometimes screw things up if it was done by an idiot.
 
I only bought the car a few days ago so I don't know about if it been remapped.
I just can't figure out why the revs so sluggish under 2k but then perfect after that.
If I drive the car like 2000rpm is 1000rpm and 3000rpm is like 2000rpm then it's almost normal to drive.
I could make more sense of it if it ran fine under 2000rpm and ran sluggish after that, but I can't understand what would cause the opposite of that !

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I will have to check for a blockage, but I can't understand how the blockage would clear after 2000rpm and then the engine is fine and pulls very strong once the turbo kicks in.

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Whiteakita said:
...I can't understand how the blockage would clear after 2000rpm and then the engine is fine and pulls very strong once the turbo kicks in.
Yeah, fair point. But then maybe we come back to the turbo... when cold can you clearly hear a ghostly whine as it spools up around 1300/1400RPM?
 
I can't hear any noise from the turbo at all even when I'm pinned to my seat at 4000rpm.

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It feels like the turbo only starts to spool around 2500rpm. Which makes me think it's the vanes stuck in the turbo, but can't understand how the turbo can make the car rev slowly under 2000rpm but then rev normally after that even when stationary.
I've basically got to keep the car above 2000rpm at all times when driving or it's just flat and the car slows down.

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Well I'm getting somewhere !
If I pull off the two vacuum lines that go to the boost selonoid the car drives much much better under 2000rpm but after that it's a bit flat.
Does this point to the selonoid being faulty ?

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