Intake Manifold Pressure Vs Atmospheric Pressure Error?

[mr_boks]

Hi All,

I have recently had my engine management light come on when i start my Verso 2.2 D4D. The car starts fine without any struggle. Then when i start driving, the TRC OFF and VSC lights come on as well. There is no struggle in driving either.

This is intermittent and sometimes the lights go away. I have been to a local garage who specialise in diagnostics and the problem code was P0400 (Exhaust Gas Recirculation Flow Malfunction). This check was done when the error lights were off. The mechanic noted that the EGR was working fine (he cleaned it for me anyway), but the intake manifold absolute pressure was reading 78kPa at idle and the atmospheric pressure was reading 98kPa. He was no expert in Toyotas, but said usually at idle these two readings should be the same. He said possible error could be with the intake manifold pressure sensor but could not say for sure.

Does anyone have any idea if this or anything else could be the problem? Or if the Intake manifold pressure sensor needs changing, how much would it cost?

Update 23/9/14: Just had confirmation from Toyota dealer - "78 is low it should be around atmospheric pressure"

[mr_boks]

I changed the MAP sensor (got one from Toyota car breakers for £40) and that too was giving a reading of about 77-79. I had the independent garage check the MAP Sensor figures on another like for like verso and the MAP reading was 78 on that too.

So I conclude the MAP Sensor is not throwing the fault (i.e. P0400 - EGR Flow Malfunction) .

Just yesterday found a Toyota Service Bulletin (Ref No: EG-7043) for the very problem. It seems the ECM was throwing the problem for pre-March 2007 models and needs an update.

I have contacted Toyota Bury today. First they quoted me for cleaning the EGR (£140+) despite me telling them about the Service Bulletin. I told then the EGR was already cleaned by the independent garage (£20), so they said they will ring back to quote for an ECM update.

Are they right to charge for something that they acknowledge is a fault on Toyota's part?

EG7043.pdf

[Devon Aygo]

I changed the MAP sensor (got one from Toyota car breakers for £40) and that too was giving a reading of about 77-79. I had the independent garage check the MAP Sensor figures on another like for like verso and the MAP reading was 78 on that too.

So I conclude the MAP Sensor is not throwing the fault (i.e. P0400 - EGR Flow Malfunction) .

Just yesterday found a Toyota Service Bulletin (Ref No: EG-7043) for the very problem. It seems the ECM was throwing the problem for pre-March 2007 models and needs an update.

I have contacted Toyota Bury today. First they quoted me for cleaning the EGR (£140+) despite me telling them about the Service Bulletin. I told then the EGR was already cleaned by the independent garage (£20), so they said they will ring back to quote for an ECM update.

Are they right to charge for something that they acknowledge is a fault on Toyota's part?

If your car is out of warranty then yes, if you have full Toyota service history and a good relationship with your dealer then they may offer the ECU update FOC as a gesture of goodwill if not expect to pay.

[mr_boks]

Thanks Devon Aygo. I have recently acquired this car. It has full service but not with Toyota.

Rang Toyota Bury this morning. Been quoted £80 + VAT for an ECU update and half of that of they hook it up and discover the ECU software is up to date.

Booked for Friday. Will keep posted.

[mr_boks]

HI All,

Updated the software on Friday (5/12/14) and the MIL light did not come on over the weekend and the drive felt subtly different. However, this morning (Monday 8/12/14), the light came on again whilst I warmed up the car.

Hooked up my smartphone diagnostic app and same code as before (P0400).

Before the software update, I (or the diagnostic expert mentioned above) was unable to wipe the fault code, but this time i was able to clear the code via the smartphone app. Restarted the car a few times and no light. Could it be the EGR is catching due to cold weather, which gave a momentary fault code?

[mr_boks]

HI All,

The MIL light came back on today, but once the engine sufficiently warmed up then restarted, it went off. Performance-wise, its spot-on.

Devon Aygo: you mentioned something about "EGR cooler modifications" in http://www.toyotaownersclub.com/forums/lofiversion/index.php?t160190.html . What is this? And do you think Toyota would have done this without prompt from me when they did the software update?

[Devon Aygo]

HI All,

The MIL light came back on today, but once the engine sufficiently warmed up then restarted, it went off.

Devon Aygo: you mentioned something about "EGR cooler modifications" in http://www.toyotaownersclub.com/forums/lofiversion/index.php?t160190.html . What is this? And do you think Toyota would have done this without prompt from me when they did the software update?

The answer would be no! the bulletin you mentioned above is an old bulletin which has over the years been updated and replaced by the current version EG-0041T-0412 it is in this bulletin that includes replacement of a large amount of parts to fix P0400 that i referred to on the link you gave.

Toyota extended the warranty for this up to 7 years/111946 miles beyond these numbers the repair is extremely expensive requireing in excess of 30 parts including EGR's EGR cooler modified fittings and pipes, Intake manifold, Injectors etc all depending on the outcome of over 17 pages of pre-checks & diagnostics the repair is also very labour intensive depending on car, in excess of 8 hours on a Verso and more than 12 on a Rav. This repair costs around £2000 at warranty rates to Toyota so a retail bill for this modification would easily cost £3000 + by the time VAT is included aswell.

Toyota bulletins are designed to offer 1 time fixes so sometimes are not the most economical way to fix an issue, P0400 is most commonly caused by a blocked EGR circuit incl intake manifoild or faulty EGR valves, whilst time consuming you can remove the EGR cooler and soak in an Ammonia solution ( at least 12% ammonia in solution ) to remove baked in carbon deposits which can prevent ( for a time ) P0400 form returning assuming the EGR valves are not faulty.

I am assuming you have a standard 2.2 and not the 180bhp version and have attached a picture of the EGR setup to show just what needs removing and cleaning. To clean the EGR cooler block/seal one end then fill with Ammonia and leave for one hour then drain and repeat until no more carbon soot is washed from cooler once the Ammonia drains clean flush with water in both directions until it runs clean.

After this you need to check if the cooler has sufficient flow to be reused, select a hose/tap that can output at least 24 litres per minute ( check by timing how long it takes to fill a bucket of a known capacity ) then confirm that the valve allows at least 12 litres of water through in 30 seconds if not try cleaning again ultimately replacement of the cooler may be required if through put does not reach 12 litres/30 seconds

[mr_boks]

Thanks Devon Aygo. You are a credit to this forum with your in-depth knowledge of Toyotas.

I am a little disappointed with Toyota Bury though. When I mentioned fault code P0400 and Technical Service Bulletin EG7043, I would expect them to explain what you did above and help me make a more informed decision.

I have tried searching for the TSBs you mentioned above but unable to find them. I have written to Toyota asking for copies.

[Devon Aygo]

You can access repair manuals & technical service bulletins at www.toyota-tech.eu this is Toyota's public access technical site, access can be purchased by the hour, day, week etc, all info is downloadable as PDF though so an hours access is probably long enough to save most things you'd need.

[mr_boks]

Hi All,

Attached is the TSB mentioned in one of the above post. I have to admit its a very technical document to understand for a lay person.

The MIL (P0400) has started to come on again after a few weeks of absence and the performance of the car has slightly dipped as well.

Spoke to Toyota Bury who say they want to do a full diagnostics at a cost of £105.64 to determine the problem. I was hoping they would do it free on a good will basis since i only used them recently to do a software upgrade for the same problem.

My only fear is that I'll pay them and they will tell me what I already know and tried to explain.

I'd love to have my car running without any problems, but it seems the cost has a potential to spiral (especially taking into account what Devon Aygo said above).

Any suggestions?

EG-0041T-0412_IR.pdf