EGR valve blanking/cheating

[PeteH]

This afternoon, I hade a good look in the engine bay, and noted a split in the end of one of the vaccuum pipes, which I have taped up with self amalgamating tape. The codes I have cleared using my Laptop. We now await the next run, to see if the fault comes back.

 

[joka250]

Hi

Long story, short, Saturday last the EMC came up on the Dash. Called out the RAC, the guy, took some readings :-

Diagnostic Codes

RAC DIAGNOSTIC SYSTEM

System Type: ENGINE

Name: EOBD

DTC: P0638,Throttle actuator control (TAC) , bank 1 - range/performance problem

System Type: ENGINE SYSTEM TEST/VALUES

Name: F1AE0481D - BOSCH EDC16C39 CF4 EOBD - 2.3L - 88 (120)

F1AE0481N - BOSCH EDC16C39 CF4 EOBD - 2.3L - 96 (131)

F1AE3481C - BOSCH EDC16C39 CF4 EOBD - 2.3L

F1AE3481D - MARELLI 8F3 CF5/EOBD - 2.3L - 96 (131)

F1AE3481E - DIAGNOSE - 2.3L - 109 (148)

F1AE3481G - BOSCH EDC16C39 CF4 EOBD - 2.3L - 81 (110)

F1AE3481G - DIAGNOSE - 2.0L - 81 (110)

DTC: P0530,AC pressure sensor

DTC: P0638,Throttle control valve

DTC: P0401,EGR valve


Ignore A/C pressure sensor code, its probably just needing some gas.
However, Throttle control valve and EGR, codes are a bit of a worry.
Having read the thread (not all of it) It would appear that at the very least a Physical clean may be required. Before I go down the road of ripping lumps of Engine off, on the driveway in the cold. Has anyone ever achieved success with "Engine Cleaners" i.e. Wynns etc?. Even if it just gets me into the new year and milder weather.
The RAC guy, deleted the codes, and E-Mailed me the printout, The EMC light is back on again, so it looks like it is not a "one off".

In the past I always used and recommended Forte products, in my opinion the best. Not easy to source but worth while.

 

[PeteH]

Well That didn't work!. The Dreaded EML is back.! Next stop, Throttle body I suspect. Fiat £300+Vat!!!. Seen a couple of promising ones on Flea bay between 195 to 255 GBP but reckon I need to remove the existing one first, to be able to find a Part number. Hey-Ho That`s SWMBO` Crissy pressy?..

 

[TerryL]

In my case (Ducato 2.3), the apparent EGR issues were caused by the failure of the throttle body. The EGR system was fine.

Me too - long story but after a couple of "tries" centered around the EGR valve my localish Fiat dealership diagnosed throttle body - fitted a new one, problem solved.
One of the tries involved a chemical cleaning procedure which, although it didn't solve my problem, did seem to make the motor run smoother and quieter.

 

[PeteH]

Decided to carry out some practical tests, Removed the inlet hose to the Throttle control valve and managed to see with a mirror that the flap v/v was clean and appears to work, Also had a good look at the EGR with an endoscope. Cannot see anything Physical. Connected the Computer via USB the the OBD port and ran Multiecuscan Software. Powered up and the EGR operation appears normal as does the Throttle control valve, with the exception that the re-action of both looked to be slow? Watching via the mirror the Throttle valve closes with a snap and appears to open fully as indicated by the reading on the laptop.

I then removed the Plug from the Solenoid, which instantly brought up the MIL. Turning attention to the Solenoid I removed it from the Vehicle and bench tested it with a Battery (13.2V). Blowing through the ports whilst connecting and disconnecting the power made no difference. So I am assuming the Solenoid is at Fault. There are only two wires so if it don't open and shut it is likely that that is the issue?.

Bite on the bullet time, Just ordered New Solenoid off Flea Bay £60, delivered Fri/Sat. Best price seen, and the correct Part no as On the existing one.

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[PeteH]

Update. Solenoid arrived and fitted, But a further Mystery. Whilst waiting for part to arrive I Took some Readings on the wiring Plug, Ignition On 8.65V, Engine running 10.85V. I know it`s a CANBUS system, but would have expected to find 12+V (battery Voltage)?

Ran the Diagnostics after fitting and the EGR and Throttle valve Numbers are OK and respond to accelerator (I Think). But there is still a lag of nearly 1minute before the readings return to zero, after the accelerator pedal has closed?. MIL light out (again). I now have to take it for a longish run to see if it re-appears.

 

[PeteH]

Out of curiosity, In case I have to go the Throttle body or EGR route. Does anyone know what the Correct Part Numbers are for the EGR. and the Updated Throttle Body?

 

[Stollysmith]

Morning all, after much deliberation I fitted a blanking plate to my Mk6 transit and I can say that it made a noticeable difference to the engine running on ‘ the round the block test’. Only took 5 mins with a 10mm spanner so easy to remove if in the long term it proves problematic. Time will tell !

 

[Techno]

Out of curiosity, In case I have to go the Throttle body or EGR route. Does anyone know what the Correct Part Numbers are for the EGR. and the Updated Throttle Body?

I think its only the 3 litre that has an updated throttle?

 

[PeteH]

I think its only the 3 litre that has an updated throttle?

Yes, My understanding from reading here and elsewhere, is the the "Revised" version with the operating control on the side, is a replacement for the one with the control underneath but requires an adapter cable?. According to several sources of supply they are a direct fit. And are possibly already fitted to later (post 2008) 2.3 Engines?.

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[TerryL]

When Fiat changed my throttle body the service manager told me there was a revised part, but they couldn't get one - on long back order with the factory. However they'd got hold of a (new) original part and had been able to modify the wiring harness (that's what he said anyway) which apparently also saved me a bit of cash. Hope that doesn't mean it's going to happen again, although he also said they'd modified the bulkhead to stop the original cause of the problem.

 

[Guigsy]

My understanding is that Fiat has gone through quite a few revisions (5? 6?) of the throttle body used on the 2.3 since 2007. Issues include water ingress in the servo, water ingress in the electronics, the actuator being weak and the butterfly's axle breaking. The latest version which is being used on the current models for the last 3 years has finally been pretty reliable. About 6 years ago, there was a change that requires a different connector, but lead from the loom to work with the new style connector isn't hard to find.

My 2007 van now has the latest TB design. I think it had already been changed some point before too. Hopefully it won't need doing again for a long while as it's an expensive part and takes at least a couple of hours for a competent mechanic... and longer if any of the studs aren't seized.

 

[Techno]

My throttle valve is now permanently lighting the check engine light.
(P0638 Throttle Actuator Control Range)
I believe that all my efforts to prevent water ingress were good but perhaps the corrosion within the motor body was already advanced enough that it was doomed to fail eventually.
I have bought the later Pierburg unit complete with adapter cable. Once I've fitted it I will disect the motor of the older Wahler unit to establish the issue.
£182 delivered

Some years ago now buy today the Pierburg is barely any dearer but now from UK sellers
https://www.ebay.co.uk/itm/Fiat-Duc...-Body-Cable-/272837592969?hash=item3f86634789

or £11 less without cable

 

[taffybloke]

My Tafmet EGR valve blanking device that I fitted in Feb 2015 failed last week giving engine light on and fault codes for MAF and EGR but the van was running fine, I was unable to clear the codes until the Tafmet device was removed.
Tafmet have asked for the device to be returned to them, which I have done, so now waiting for a response but I don't think they sell this version now.

EDIT. just checked and they still sell them, It wasn't there a few days ago when I looked.

Mike

 

[tonyidle]

The people who designed it were no idiots, reason for it being there !

There is a reason and it has nothing to do with performance or economy. It feeds exhaust gas back into the inlet manifold to cool combustion (never a good idea with an ICE of any kind) and reduce NOx emissions. Apart from any effect on economy and performance it slowly gums up the inlet manifold and, eventually, the inlet valves. A high mileage engine (150K+) will have the inlet manifold reduced in internal diameter by at least 50%. NOx emissions are not measured at MoT time and as far as I'm aware the ECU has no sensor to determine levels of NOx. It wants to see the EGR valve operating but it cannot see the effect. So the answer is to blank the exhaust to inlet passage but leave the valve in place doing nothing. EGR is such a brilliant idea that it has been replaced by AdBlue which, as it's injected downstream of the exhaust manifold, has no effect whatsoever on engine performance and economy.

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[tonyidle]

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[Sean FSY]

So I've had the EML come on in the MH. autotrail Arapaho with the 3.0 160bhp engine. 2007 van with 19k miles. Problem Started a couple of weeks ago, it cleared but after a week the EML light is back on. Codes P0235 turbo boost sensor and P0638 throttle actuator control. After speaking to Techno I have ordered the updated throttle actuator housing model and look to change over. If it asnt been done is it worth while doing the EGR blanking off? Also does anyone know where the Boost Pressure Sensor is?

 

[andy63]

Also does anyone know where the Boost Pressure Sensor is?

I don't know that engine but the turbo boost sensor will be located on the inlet manifold or on a short pipe that feeds it.. most probably close to where the exhaust gas recirculation pipe feeds into the manifold..
if your egr valve is electronically controlled its likely just blanking it will not be enough...ie it would start to generate fault codes ..
Andy

 

[Landy Andy]

Just to bring this up to date. Fiat Ducato 2.3s do suffer from egr failure and that goes on to cause other issues,