Help On Fault Code P024A, P024B & P024F

[Tony Nash]

Hi All,

I'm hoping that someone on here might be able to help as I am pulling my hair out.

On Monday night I was driving my 2005 1.6TDCI Focus home from work - about 20 miles with the majority on the motorways - just as I cam off the motorway I lost all power and the car started to belch out black smoke from the exhaust and the engine management light came on. I managed to get it onto the hard shoulder and stop. As soon as I tried to accelerate again the acceleration was very jerky and then it sorted itself out (probably due to slower speeds on residential roads).

Anyway I managed to get it home and put the fault code reader on it (ELM 327 and easyODB2 on my laptop). The faults recorded were P024F Stored and P024F from last cycle. I looked these up on various internet sites but nothing conclusive - air bypass valve position sensor circuit high input seems to be the definition but no soultion.

Some sites were mentioning the EGR valve so I removed and cleaned this (wasn't too bad as I had it cleaned a while back). Cleared the fault code and the engine management light and too it for a spin - no lurching or smoke but the acceleration was a little hesitant at low revs.

Next day the problem is back again (the other half was driving so I wasn't very popular). I took it down to my local garage on Wednesday morning and got the same fault, infact it was so bad I couldn't get it up the hill to the garage.

Its now been in for 2 days and my mechanic hasn't been able to find the cause of the problem - no split pipes, nothing abviously wrong which to me implies a sensor fault or something internal. (He got the same codes when he read them on his fault code reader).

Ford are useless - their answer was "those aren't our fault codes"

Does anyone have any idea where to start looking on this????

I had the Turbo replaced to Ford's Technical service Buliten last year (about 8000miles ago) so I'm hoping it's not turb0 related.

Car has done 137k mostly motorway miles, DPF replaced at 110K, Turbo at 130K, Alternator at 137k (last week!) Air fliter 135k, fuel filter - not sure when it was replaced probably 90K,

Any suggestions greatly received.

Tony

[Mike77]

Ford will always say they aren't their codes because THEY want to run a diagnostic on it THEMSELVES. Will prob charge you about 80 notes for the pleasure to.

[Stoney871]

As stated, Ford won't take your word on codes and will insist on doing their own diagnostics (no profit for them else).

I'd be leaning towards the EGR valve sticking open and allowing too much exhaust gas back into the system and choking the engine.

[Tony Nash]

If the EGR valve is replaced with a new one does the ECU need to be reprogrammed or is it plug and play?

How would I tell if the current EGR is stuck when I've got it off the car? Can the body and soilenoid be seperated so it can be fully cleaned? I only cleaned the ports of the EGR valve when I removed it earlier in the week.

Could the EGR cooler be blocked? Would this give the same fault codes as EGR buggered???

[Tony Nash]

^{Had a bit of a brain !Removed! last night, if the EGR valve is faulty and the cause of the trouble, could I fit an EGR blanking plate to eliminate the EGR valve from the system? I know it would still bring up the fault in the ECU but if the physical fault of poor running is cleared up it would confirm the EGR valve being at faulty then I could replace it.}

^{Does this seem logical?}

^{It seems a cheaper way rather than £120 for an EGR valve only to find out it doesn't clear the problem.}

^{Also a friend of mine said the symptoms sound like it could be the MAF sensor (he had the same symptoms on his VW Passat). Does this seem reasonable?}

[IINexusII]

^{Had a bit of a brain !Removed! last night, if the EGR valve is faulty and the cause of the trouble, could I fit an EGR blanking plate to eliminate the EGR valve from the system? I know it would still bring up the fault in the ECU but if the physical fault of poor running is cleared up it would confirm the EGR valve being at faulty then I could replace it.}

^{Does this seem logical?}

^{It seems a cheaper way rather than £120 for an EGR valve only to find out it doesn't clear the problem.}

^{Also a friend of mine said the symptoms sound like it could be the MAF sensor (he had the same symptoms on his VW Passat). Does this seem reasonable?}

yes you could. its very easy to do and would make your car smoother on lower revs too

clean the egr as much as you can with some sort of cleaner and blank it off

[Tony Nash]

Thanks for the reply IINexusII

I had the valve off on Tuesday night and gave it a good clean then and to be honest there wasn't much carbon build up on it, no sludge as I've see on pictures of other EGR's.

I'll order a plate off eBay as it's only a couple of quid for a stainless steel one and if it doesn't work I haven't lost too much.

Is there any way of testing the operation of the valve when it is off the car?

[jeebowhite]

not particularly but blanking is the least painful option!

[Tony Nash]

Ok, so here is an update on the Focus relating to the P024A/B/F fault codes - hopefully this will help someone else out in the future........

The P024 faults all relate to the assembly highlighted in the picture below (I'm not sure what the technical term for it is but it seems to regulate the mix of air from the intercooler & EGR system back into the turbo).

It is made up of a manifold, 2 flaps and 2 electric motors. The motors open and close the flaps regulating the amount of air flowing from each of the pipes.

Here is a close up of the assembly.

To remove it you need to undo the 3 jubilee clips - red arrows (1 of them is under the unit coming from the intercooler). Unplug the 5 multi plugs - green arrows. There are 2 bolts holding the unit onto the engine block - one is on the left hand side and is easy to see, the other is at the front of the car and is under the air con pipework. Remove both of these, then remove the unit by pulling up and away from the pipework.

When you have the unit on the bench you can see the 2 flaps and can test their operation by pushing on the flap. They should be free moving and spring shut. (Sorry didn't take any pictures of this)

When I removed mine the smaller of the 2 flaps was stuck shut. I slackened off the bolts holding the motor onto the manifold and it allowed the flap to move. However when it tightened the motor bolts the flap stuck again. I ended up adjusting the position of the flap on the motor shaft by slackening off the 2 torx bolts that held it in place and adjusting it until it moved freely.

Whilst I had the unit off I gave it a good clean out (it wasn't too bad but I thought whilst it is off.....) Only bit to watch is there is a sensor in one of the openings of the manifold (its the one connected to the green multiplug in the picture above) so be careful when cleaning near this.

As the Haynes manual says refitting is the reverse of removal.

I cleared the fault codes stored and turned off the engine management light using the software I have on my laptop and took the car for a run. So far no fault codes, no engine light, no smoke and no hesitation.

After this success I have also fitted an EGR blaking plate and cleaned the MAF sensor.

I've done all these fixes/changes in stages and test run the car at each change so I am confident that each are making an improvement.

The car is now back in general service and completed the 20mile hack to work this morning without any issue. The MPG has increased considerably as well. It was reading 36mpg after half a tank and this has risen to 41mpg after just 20miles extra driving (it's never been great but I have always put this down to it being a high mileage car (137k) but perhaps it has been down to a gradual failure of these components - who knows!!.

Tony

[Roely]

Dear Tony,

Quite honest I'm a Volvo V50 (1.6, 2006) owner, but with the same block and same fault code.

I had almost the same problem, the difference was that the small valve did close.. almost completely.. but not enough.. So I took the valve out and discovered a broken plastic item that should hold the spring.

A bit of epoxy plastic glue did the job! The valve is closing completely again.

I cleared the fault codes and it looks like a solve!

Thanks for your detailed description!

[fr0styTDCi]

Hi All,

Old thread I know but may be of use to someone experiencing similar problems..

I'm currently experiencing the following codes:

PO234 - Engine over boost.

P2141 - EGR Throttle control circuit.

P024A - Air Cooler by pass control - A range performance.

P024B - Charge Air Cooler by pass control A stuck.

Ford have diagnosed this as a faulty throttle body which is the part Tony posted a picture of.

Ford want £567 parts and labour to replace it.

The Ford part number is 1556103, the lowest I have found it for was £432.24 delivered from Ford Parts UK.

I've gone down the route of a second hand one from a ford breakers in Oldham costing £81 delivered whether this was a wise move or not is still to be determined as I've not fitted it yet.

Photos show the part in greater detail.

It is known as PA6T/6I GF60

[Stoney871]

Before installing, this could be a good time to give it a thorough clean with a decent throttle cleaning spray and a soft toothbrush.

Once clean and any fluid has been evaporated/wiped away I'd dab a small amount of oil on the throtyle shaft (cotton buds are good for this).

Sent from my SM-G900F using Tapatalk

[fr0styTDCi]

Yea Its needs another going over before fitting, any recommendations on a good cleaner to use?

Hopefully all goes well and the problems sorted as its driving me mad.

I guess after its fitted ill clear the faults with forscan and take it for a good drive up the M1 for a few junctions to see if the fault reoccurs.

[Stoney871]

BG406 or K2 are pretty good.

Sent from my SM-G900F using Tapatalk

[fr0styTDCi]

Just an update..

Fitted new part this morning cleared all faults using forscan

immediately noticed better throttle responce car was much better to drive so i thought all was well.

Went for a drive on the motorway and after 1 juction fault reappeared but wasnt quite the same feeling anymore.

drove home and rescanned with forscan and the following came up

 

Any thoughts would be appreciated

 

[simcor]

Most likely culprit is the VNT vanes sticking open I suspect, I currently have the same issue, but I do get a lot of grey smoke under acceleration especially noticeable at night in the lights of the vehicle behind me. Or the VNT vane actuator is not working properly at a guess.

I really need to look at mine and sort it but the weather is pretty rubbish at the moment.

[fr0styTDCi]

Ill explain whats happening..

Its mainly when driving on dual carrigeways/motorways in 5th at about 2.5/3k rpm

Ill get a sudden loss of power almost like breaking then power will return and then disappear again also a hissing sound when accellering until i restart engine and alls fine again.

Is this the same issue your experiencing?

 

[simcor]

I don't have that issue no.

Are you getting any smoke from the exhaust? Hissing noises are usually an interviewer hose split. That would give a lack of power and a hissing or whooshing noise. It may be a small split that is only opening up at the rev point you mention possibly.

Just an idea to look into.

[fr0styTDCi]

Theres no smoke, car drives fine until the fault i discribed arises then as soon as its restarted its fine again just rather annoying when im driving and it happens..

Iv seen good thing about terraclean:

http://www.tunagarage.com/terraclean.html

Could possibly help with de-carbonising the turbo vanes if that is the issue

[Miffeltoffel]

TL;DR: Take apart, clean the housing, especially the sensor, done!

Hi, since this thread is listed quite high on Google, when looking for a solution to the P024F fault code, I figured I'd post what worked for me. Thank you Tony Nash and fr0styTDCi for your input and very instructive posts. I'll shamelessly steal your images to illustrate my own experiences, hope you don't mind!

I live in Sweden and own a Mazda 3 (gasp!) with the same engine as the one discussed in this thread. One day, the "Check engine" light came on and my OBDII scanner showed P024F as the culprit. Tried to reset, but to no avail, the fault code reappeared 30 seconds later.

So I took the aforementioned unit off by removing the 2 jubilee clips indicated by red arrows, and then rather than removing the topmost jubilee clip, i removed the 3 bolts indicated by yellow arrows (it came off easier that way), then remove the 3 bolts indicated by the green arrows. Topmost is the extension of the bolt holding the top engine cover in place, left and bottom are below the unit.

My chokes (the flaps) seemed to be working fine, although there was a lot of oil in the unit, very much so on the sensor indicated in the second image. I cleaned the housing and the sensor by spraying it thorougly with brake cleaner fluid. After that I reassembled, reset the fault code and lo and behold, no more Check Engine light! Driven for about 100km since then so hopefully the problem can be considered solved.

[Miffeltoffel]

Alright, so back again.

 

The above post did not solve my problem, albeit it did alleviate the symptoms for a while.

Since then I have replaced the whole housing, so as to make sure that none of the actuators or sensors were at fault, however the problem persisted.

I also cleaned the DPF to no avail, and somewhere along the way I purchased Torque Pro (all in all a very worthwhile purchase), which revealed further fault codes which did not show up in the free version, namely P0089, P0404 and P1180, these indicating that there is something wrong with the EGR valve.

So i located the EGR valve in accordande with this clip (it located behind the engine to the right, just behind the fuel filter. It's fairly accessible, if you just remove the plastic top cover)

https://www.youtube.com/watch?v=NC-b-e6fUrU

And removed the electrical unit fastened with three torx bolts as according to this image

and checked the state of it, as described in this video (all in all, it should run smoothly, not stick or rotate jerkily) DISCLAIMER: NOTE WHICH WAY OT WAS WHEN REMOVED SO THAT YOU ASSEMBLE IT CORRECTLY.

https://www.youtube.com/watch?v=eWqjHsLBY0k

My valve motor behaved as the broken one, so I ordered a new complete valve.

To remove the whole valve, just remove the two bolts shown by pink arrows in this image and open the clip by sticking a flat head screwdriver where the green arrow shows and twist it gently. It should pop open fairly easily.

To install the new EGR , stick the topmost bolt through the EGR valve and the seal, rotate it slightly away from the pipe where the clip was and fasten the bolt slightly. Now you can rotate the EGR into place so the the pipes interlock (DON'T FORGET TO ADD THE CLIP ON THE PIPE BEFORE ROTATING INTO PLACE), then fiddle the seal into place for the second bolt and fasten both. Reclosing the clip is a bit fiddly, but I used a pair of polygrip pliers to close the clip and a screwdriver to push down on top of it to make it lock.

I've now driven for about 200km with no fault codes stored in the ECU, which is a lot more than anytime before. And in contrast to my previous post I've actually checked the fault codes, not just the check engine light. Was a bit fiddly, since P024f doesn't directly imply that the EGR is at fault.

So, hopefully this solves the problem, I'll report back if it doesn't.

 

[Danmx3]

Hi, I also have been getting this error code. I removed my unit and found that the larger butterfly throttle plate is in the open position. This is also the case with a salvage part I got from a volvo. Is it meant to be in open position or are both for certain meant to be in closed position?

[LeoMondeo]

Hi. I'm recently having this problem. I have a 2009 Focus Wagon with the 1.6 TDCI engine (109 hp)

I have the following codes:
P0407 - Exhaust Gas Recirculation Sensor B - Circuit Low
P024A - Change Air Cooler Bypass Control - Range/Performance
P024B - Change Air Cooler Bypass Control - Performance or stuck off
P024F - Change Air Cooler Bypass Control - Circuit High

 

The code P0407 comes back as soon as I clean the DTCs. After some seconds, errors P024A, P024B and sometimes P024F do show up. The first three as Present(Permanent) and P024F as Intermitent. Car seems to work normal (no Limp Mode), but after some time, the Check Engine light comes up. Also, if I try to accelerate hard, the car will stall (sometimes at redline, other times just above 3500 RPM). The stalling happens regardless of the Check Engine Light and if I just wait one second, I can start the car again (if I start immediately after, the car cranks but does not start).

The problem seems electric, as the errors come back even with the car off and ignition on, so I guess the problem wouldn't be air leaking from the intercooler tubes or anything, right?

I have tried many different things to solve the problem and I'm pulling my hair out. I've searched for the problem everywhere I could (including this post).

Here's what I have done so far:

1 - Removed the throttle body thingy and cleaned every sensor and made sure the butterfly valves were opening and closing properly (and sealing perfectly when closed). I even disassembled the butterflies from the motors and tested them in the car (with the car off, obviously, my scan tool has a "self-test" function), in this test, I noticed that when one valve closes, the other opens (one of them allows the gases from the EGR to enter the intake, the other bypasses the intercooler, as far as I know), I do not know if this behaviour is normal or not, either way, I do know that the butterfly valves are opening and closing properly.

2 - Went ahead and replaced the EGR. I tried cleaning mine (it was not so dirty, but I did it anyway), but the errors persisted. I got an aftermarket one from Autodoc (it was not very expensive, so I did it). Even after replacing the EGR (and resetting EGR values with my Scan Tool), I got the same DTCs as before (and the same ones I get if I simply unplug the EGR valve).

3 - I got a diagram of the engine computer and its conections. Tested all wires from the EGR and from both butterfly valves to the ECU with a multimeter. Everything seems ok. I also checked all fuses even remotely linked to the engine management, they are all in perfect state.

 

If anyone can give me any hint of something I am missing, I would be very thankful. I enjoy my Focus so much but this problem is really wearing me out.

Thanks everyone.

[LeoMondeo]

Just solved the problem. I checked all wires and the ECU internals after I replaced the actual EGR valve. Nothing seemed off. Even tough there was no visible problem with the butterfly assembly thingy, I got a used one for cheap and decided to swap it. After I swapped the butterfly assembly (and reset the EGR adaptation values with the fault scanner), the trouble codes went away and thankfully did not come back (before doing the swap, they would return seconds after clearing the faults).

 

Hope this helps people in the future. It's a shame this throttle thingy is so expensive as a new part and one can't reliably diagnose a faulty one, I was lucky I found one on the cheap.

 

Thanks everyone for pointing in the right direction!!!