Help on the AGR Engine!!

[Si_TDi_FR]

Posting this for a Friend

I bought a mk4 1.9 tdi 90bhp recently with 82k on the clock. Drove the car after finally getting insured, and the car seems really sluggish. Top end i struggle to get over 85 and the cars acceleration is awful. If i wind down the windows i can hear the turbo working although you do not get that input of power at around 2 thousand revs like you normally do with tdi's.

Anyone got any idea's? I've been told it could be the turbo actuator valve?

Thanks in advance!

At the moment we have unplugged the MAF sensor and had made NO difference to the drive it all.

The turbo is fine, can hear it spooling up and sounds exactly the same as my FR. There are no loose boost pipes as there is no whistling or smoke from exhaust.

So is it basically a fudged MAF sensor or is there other things to try out?

Much appreciated Guys

 

[Viking]

Maf sounds to be goosed to me. First thing to change.

 

[Si_TDi_FR]

If the MAF was shot would it still make full revs? On my old 206 1.4hdi if i unclipped the MAF it would only go to 3.5k or is it different per manufacturer?

 

[MJ]

Either maf or sticking turbo vanes.

 

[Si_TDi_FR]

What do you mean by turbo vanes?

 

[MJ]

the internal workings of the turbo, they work like trapdoors and if they stick then this limits or cuts off power.

 

[Si_TDi_FR]

Any cure to this then?

 

[Si_TDi_FR]

I don't think the 90bhp engine has a VNT turbo, only VNT turbos have movable vanes therefore only VNT turbos can get sticky vanes. Does sound more like a MAF thing to me, or if it's smoking a lot then possibly a split pipe going into the side of the EGR valve (I had a pipe pop off my Mk4 Golf TDI90 and that caused the same symptoms you're getting, lack of power etc, but with a lot of black smoke as the engine seemed to be overfuelling as not all the air it was requesting was actually getting into the cylinders). You say there's no smoke though so probably the MAF.

If you can find someone with VAGCOM then get them to log block 003 in the engine controller with their foot down in third and you should see the requested and actual figures either very close to each other or with the actual figure higher. I'd do it but I don't know where Northallerton is, North Yorkshire rings a bell? Near Middlesbrough?

Yeah the boost pipes are deffo on as i knew if they were loose or split it would be smokey but it doesnt give off any smoke at all.

Well i think he is going to be ordering a Bosch MAF for it and will fit it and have fingers crossed. When it arrives do we just unclip original and refit the new one in its place, clip it up and take for a spin?

Thanks Guys

 

[Si_TDi_FR]

Still no luck, MAF replaced and is exactly the same and coming up with the same fault codes on VAGCOM which are...

Car - 2000 mk4 golf se tdi (90bhp)

17569 - Manifold Temp Sensor (G72): Open or Short to Plus

17564 P1156 Manifold Abs.Pressure Sensor Circ. Open/Short to Ground

17664 P1256 Engine Coolant Temp.Circ Open/Short to B+

17552 - Mass Air Flow Sensor (G70): Open or Short to Ground

Readiness: N/A

 

-------------------------------------------------------------------------------

Address 03: ABS Brakes

   Controller: 1J0 907 379 P

   Component: ABS     20 IE CAN  0001

   Coding: 03304

   Shop #: WSC 00028

1 Fault Found:

18256 - Please check DTC Memory of Engine Controller

            P1848 - 35-00 - -

VAG-COM Version: Release 409.1-US

 

[Si_TDi_FR]

Bump

 

[Si_TDi_FR]

Anyone ?

 

[Muttley]

AGR has a wastegate turbo, no vanes.

With those VAGcom codes your engine fault light should be lit. If it isn't check out the dash panel to see if it's been blanked off.

The VAGcom codes suggest that your manifold air temp and pressure sensors are both disconnected or faulty. These sensors are housed together in a single unit that is attached to the inlet trunking between the intercooler and the engine manifold. Look on the left side of the engine bay, in front of the cambelt housing; the sensor assembly is attached to the plastic pipework.

If you're very lucky, it's just been disconnected. If not then a new sensor assembly might be needed. I'd want to check out the wiring too, though - the fact that both sensors have failed indicates a common fault.

Lack of manifold pressure sensor will put the engine into limp mode - the ECU can't tell what boost pressure is there, so reduces it to a minimum to safeguard the engine.

 

[Si_TDi_FR]

Could you do a quick photo of the location these sensors are meant to be please? It would be greatly appreciated

 

[Si_TDi_FR]

AGR has a wastegate turbo, no vanes.

With those VAGcom codes your engine fault light should be lit. If it isn't check out the dash panel to see if it's been blanked off.

The VAGcom codes suggest that your manifold air temp and pressure sensors are both disconnected or faulty. These sensors are housed together in a single unit that is attached to the inlet trunking between the intercooler and the engine manifold. Look on the left side of the engine bay, in front of the cambelt housing; the sensor assembly is attached to the plastic pipework.

If you're very lucky, it's just been disconnected. If not then a new sensor assembly might be needed. I'd want to check out the wiring too, though - the fact that both sensors have failed indicates a common fault.

Lack of manifold pressure sensor will put the engine into limp mode - the ECU can't tell what boost pressure is there, so reduces it to a minimum to safeguard the engine.

We have found a loose plug tonight, i did some searches on google and found the forge fitting guide for the MK4 golf and saw the MAP location.

After moving washer bottle there is no sensor at all as its not the PD engine and according to google the AGR engine doesnt have a MAP sensor. But if it didnt it wouldnt come up on the VAGCOM faults

 

[Muttley]

You have a single side mounted intercooler in front of the driver's side front wheel. The inlet trunking comes from the top of the intercooler to the inlet manifold on the back of the engine, running along the side of the cambelt housing at the top of the engine. The temperature/pressure sensor should be attached to the side of this trunking, in front of the engine.

Can't take a pic right now, bonnet frozen shut. Mine is an ASV, but I think the locations are the same, at least Elsawin thinks so.

 

[Muttley]

Okay, Elsawin is not being helpful. My ASV has the sensor in the top of the intercooler, behind the offside headlight but in front of the washer bottle, visible when the bonnet is open.

Two slightly rusty screws can be seen holding the sensor unit in place.

Topmost wiring goes to the offside indicator, next one down to the washer bottle level sensor. The lowest wire run comes from the sensor, loops round behind it then follows the intake trunking.

 

[Si_TDi_FR]

We had the washer bottle out last night and to our avail there is no sensor down there

The car was a CAT D write-off but had been repaired so is it possible the intercooler had been smashed and replaced with an incorrect intercooler?

 

[Muttley]

Possible, I suppose. Was the offside front quarter where the damage occurred?

Don't know for sure where the sensor is supposed to be on an AGR engine, it might be in the top pipe. The engine is not going to work well without one, though.

Your error codes also indicated no MAF and no Coolant Temperature Sensor. MAF you know about, and you've replaced it - so perhaps the ECU needs to be reset to clear the codes, then you can see which ones come back. You did plug the MAF into the wiring harness, didn't you?

 

[Si_TDi_FR]

Yeah it has had a new offside wing, front bumper and offside light.

Yeah the MAF is all plugged in fine etc. Just found this connector in the engine bay so assumed it was with the MAP problem but its trying to find its location

 

[Muttley]

Where is this loose connector situated? Can you do a picture? Is the cable run attached to the inlet trunking?