Swapped injectors.

[TDi110]

I have swapped all 4 injectors for some that I had rebuilt, by a diesel shop
After swapping started the car with no issues.

Left idling and rev'ed every now and again, no problems.

Went for a test drive found that the car becomes very rough during acceleration or climbing a hill, anything that gives the engine a LOAD.

Checked for faults using vagcom, nothing logged.

Whats going on, what have I done wrong, if anything?

Car is a 110BhpGolf, AHF engine.

TAI

 

[DieselOx]

New nozzles as well? How many miles have you put on them? The nozzles usually need about 75 miles to run-in well, and you may also need to re-adjust the IQ with vag-com to deal with the new fuel quantity. I'd bet rebuilt injectors need a break-in as well, even with old nozzles, but I'd also bet you have new nozzles in there as well, what'd be the point otherwise?

I just had new nozzles installed in my injectors and everything cleaned, and it had a real rough spot at about 2500-2900 rpms, but after about 100 miles it cleared up and now it's smoother faster and all around more fun to drive.

 

[rdkern]

What's the iq? Nozzle size? Planet earth - north america or the real world?

 

[TDi110]

What's the iq? Nozzle size? Planet earth - north america or the real world?

Not sure on the IQ, but is untouched.
Nozzle size again is stock, not gone for bigger or anything.
From the UK.

The rebuilt injectors have had new nozzles and the pressures set, they have done less than 20miles.

But the problem feels more like its missing, starving of fuel when under load: accelerating or climbing a hill. It doesn't run rough at idle.

TIA

 

[rdkern]

You shouldn't have to change the IQ if it was good to start with and new nozzles are the same as old. However, that is "if good to start with".

Nozzles sometimes takes a few hundred miles to "seat" correctly. At least that's what I've read.

Other than that, when was the fuel filter last changed? Air filter?

 

[TDICult]

I just had new nozzles installed in my injectors and everything cleaned, and it had a real rough spot at about 2500-2900 rpms, but after about 100 miles it cleared up and now it's smoother faster and all around more fun to drive.

I changed my injectors as part of an Elsbett modification. Noticed the same roughness between 2200 RPM and 2900 rpm both on Diesel and SVO. Still has not really cleared.

Idle was smooth. Power was fine. Just not the smoothness before the change and really only an issue on hard acceleration. It might be to do with the way the pop pressure has been adjusted as I believe its a two stage injection to soften the combustion.

Also check Smooth Idle on Block 13 on VAG-COM. Just in case one cylinder is out. If power is down you may have an air leak on the copper seal. I had -took two weeks (500miles) to show, lost power but I dont think it ran rougher. Replaced washer and seal was good, power good but roughness was still there.

Hope to hear how it goes.
Colin.