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Diesel holding back at 3000 rpm

Kentm111

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Accord tourer mk7
Hi all.

Just a little help, recently I have noticed that my diesel is holding back at about 3k. And absolutly no pickup on a small incline at 45mph in 5th. And will not give me more than about 3200 in 5th (107mph aka on a tiny incline)

Equally if you allow a steady throttle build up to about 2500rpm in 1st and then give her full throttle there is absolutley no turbo surge.... most of the time.

I am checking the wastgate tomorrow and the vacuum pipe to the actuator but does anyone else know what else to poke whilst I have a bit of free time?

Use to have a td5 defender so am familiar with various colapsing of hose internals, but not aware of any lined hoses on the N22a unit.

Should say the engines it totally OEM with 158k.
 
It could be the egr valve is gunked up. My wife had the same symptoms on her Nissan Note 1.5 diesel. Fortunately egr removal was quite easy and it was full of soot. Cleaned it out and it runs really good. I still need to check the feed pipe to it when I get the chance, bit of a longer job that.
 
Try temporarily blanking your egr, it will throw an error but if the power resumes then you know that’s the issue.

could also be intake flap, turbo or even bad injectors.
 
Hi all.

Just a little help, recently I have noticed that my diesel is holding back at about 3k. And absolutly no pickup on a small incline at 45mph in 5th. And will not give me more than about 3200 in 5th (107mph aka on a tiny incline)

Equally if you allow a steady throttle build up to about 2500rpm in 1st and then give her full throttle there is absolutley no turbo surge.... most of the time.

I am checking the wastgate tomorrow and the vacuum pipe to the actuator but does anyone else know what else to poke whilst I have a bit of free time?

Use to have a td5 defender so am familiar with various colapsing of hose internals, but not aware of any lined hoses on the N22a unit.

Should say the engines it totally OEM with 158k.
Doesn't sound dissimilar to my problem with ICDTI.
 
Checked the EGR and thats fine, ive also checked the resistance on the injectors and they are all identical with about 0.4ohms.

Ive been looking at the denso boost control and I'm wondering if thats worth a poke?

More importantly, can the turbo be taken off the block without taking the engine out of the car?

Applying a vacuum to the turbo actuator, it seems to move without any real issues. But I wonder if its damaged?

Just done a 0-60 time using the OBD circuit. 13.98s. And that was trying.

Currently a small downhill at 1500 rpm in 5th it will not accelerate at all.

All help is appreciated, otherwise she will have to go as shes dangerous when trying to overtake.

Thanks
 
Checked the egr how?
 
So... not giving up I have taken the entire inlet system out and discovered... nothing. No holes no bad connections, nothing.

So went back to the EGR having checked the turbo, and found it wasnt quite fully seating, then found that the solenoid is slightly sticky so soaked it in silcone... the droped it a bent the valve inside. .

So had the fabricate a quick blanking plug between the egr and the head and found (once rest the ecu) she takes off really well... then LHM again... rest and so on and on and on.

Replacement now ordered as we at least know the issue !!!!!! Huge yeay !!
 
So it was the egr after all. This is why I suggested temporarily blanking it, far easier, quicker and would have yielded an immediate positive determination of the root cause. I wasn’t suggesting this based on random guesswork, it’s years of experience with these engines.
 
Hi all.
So I have some more information about the sluggish performance. Firstly the turbo pressure is still able to climb to 22psi in 1st but in 3rd I discovered something interesting.
If you approach a roundabout at a high speed then go from 5th to 4th to 3rd quickly , so keeping the engine rpm above 2500 there is absolutely no power when you then accelerate.
I managed to watch the turbo pressure and EGR % and noticed that the turbo would climb (slowly) to 13.3psi then flutter and drop to around 7psi and then climb to a peak of about 8-9psi. At the same time the EGR would open to around 10%. This wasn’t a 1 off but happened a good 10 times during a 70 mile drive. The turbo would never come up to higher pressure for a good mile or more but would return. If I had to over take a truck then it would seemingly do the same. To put it in context I was out dragged by a jag towing a caravan and a VW UP.
I have replaced the EGR and inspected all the hoses and intercooler so I cannot see of hear any leaks.
I am wondering if the turbo vacuum control solenoid is faulty ? Does any one know a way to test that component?
Equally, where Honda even more cleaver than I had though and not only use the EGR as a method of lowering emissions but also to reduce the exhaust gas pressure running to the turbo? Essentially making it act as a waste gate system for the VNT?
I use to own a TD5 defender which are known for a similar issue however there issue was always related to either the MAP sensor (getting gunked up) or the wastegate sticking closed. I once freed up a waste gate which solved it for a good 30K miles. Since Im told the turbo is VNT then therre might be little point in poking around too much with that. I have applied a vacuum to the actuator and it moves freeley enough. I did once work on an old Porsche which had a VNT issue, namely it snapped a guide vane but that has to be very rare I would ***ume?

All help is appreciated as normal
 
Probably totally unconnected, but, recently I had no pulling power above 2.5k revs. Had turbo off and tested, ok, Fahad tested everything, egr etc, etc, all ok. Cleaned maf and eventually changed it, no change. Air filter out, all ok full power. Finally discovered a loose plastic cover over the air box inlet was being sucked against the inlet pipe.
I only mention this in case you too could be missing something simple, good luck. Rod.
 
Well that is my hope too, But nope not this time. I have taken the airbox off entirely and no desernable difference. However a little more info, its most noticable around 2100-3200. Peak psi in 3rd is 17.7psi but will only give this at WOT for about 3 seconds or less and generally drops to about 8psi or so. I will try to see if I can use the go-pro and youtube to upload a video showing the psi and rpm link a little better than I can explain.

Any more simple to try ideas, oh and the exhaust manifold isnt cracked either thankfully.

Not sure its the turbo unit either as it gives good boost in 1st generally... I say generally as roll-on boost isnt great.

Postcards to the usual addresss
 
It could be a failing throttle position sensor, mine was giving issues for a few days before it threw up any codes.

Fuel delivery ? Have you changed the filter recently ?
 
Well we have a development !!!

On the drive to work I completely lost all power and only had tick over. I noticed that the temp gauge was very high. Limped to work (its amazing what you see at 15mph!!)

Refilled the now empty rad and then drove back. On the way home there was a noticable difference in power (and had full throttle again)

On my test location where I have been experiencing a peak speed of 45-48mph 4th gear roll on up hill... see previous posts for more details... I got 58mph.

I will see how it goes this week but on the face of it it would appear a lack of water in the cooling might have been the route cause??

Is there any sensor which tells the ecu to restrict performance if the water level is starting to run low ??

So... fixed for the moment. Will keep you posted.

Mike
 
Be aware that if your cooling system isn't pressurising the water boils at 100C, which is not the maximum on the temperature gauge. So you might think the temperature is "a bit high" but in reality you have screaming hot motor and turbo trying to offload heat to a maxed out heat exchange system.

Until you find the water leak, drive gently, and keep filling up the radiator.
 
Since engine temperature is one of those readings that can be accessed on the OBD2 interface and one of those 'in car' apps, it is quite feasible that the cars ecu will trip into limp mode if something is outside the design parameters of the engine.
 
Well after 24'000 miles (161k in total) a recon set of injectors, a new alternator which still hasnt fixed the charging issue, countless hours of testing electrical circuits, plumping, hoses and connections, replacing the front lower wish bones, drop links for the anti roll bar and no doubt lots more besides... I have finally solved the issue.. except for all of the above, I have traded it in. The final straw was it not staying on the ramps and nearly falling on me.. okay my fault but if thats not a hint to let it go I dont know what is.

So thanks for all of your help and no doubt head stratching over the last 2 years or so its time for me to bow out.

All the best in your future endevours.

Mike
 
Well after 24'000 miles (161k in total) a recon set of injectors, a new alternator which still hasnt fixed the charging issue, countless hours of testing electrical circuits, plumping, hoses and connections, replacing the front lower wish bones, drop links for the anti roll bar and no doubt lots more besides... I have finally solved the issue.. except for all of the above, I have traded it in. The final straw was it not staying on the ramps and nearly falling on me.. okay my fault but if thats not a hint to let it go I dont know what is.

So thanks for all of your help and no doubt head stratching over the last 2 years or so its time for me to bow out.

All the best in your future endevours.

Mike

You didn't spray the TPS box ?
 
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