A small issue with my mk7 2.2TDCi..

[MartinP86]

Hello there,

An annoying issue with my van that's been bothering me for a while now. It's not always there, which makes it difficult to find and solve. Here it is:

Sometimes when i'm driving the van, it seems like there's a little loss of power, you've got to press the throttle a bit further to accelerate or maintain speed so that's obvious. Now, when that happens and i want to change gear or slow down, i can also feel that those pedals are "softer". It's almost like there's air in the brake and clutch system. Obviously i checked to see if there's air in the system but there is no air. Most of the times the pedals are as hard as they should be and the van will respond to the throttle like normal. I can imagine that if there's something wrong the ECU cuts throttle response for whatever reason, but so far i haven't been able to find the cause of this issue.

Anyone ever had this with their Transit, and if so, could you maybe give me a hint as to what could be causing this? Could it for example be a small vacuum leak somewhere?

before anyone asks: I can always bring the van to a safe stop, for me there's no worries about safety but obviously there's something that needs fixing.

After a drive when i shut down the engine and press the brake pedal, i have heard some air at the pedal box but that's not been the case recently.

Hopefully some of your Transit experts can give me a hint in the right direction

[metalworker0]

Low brake fluid .. clutch and brake share the same reservoir - check level
Clutch and brake peddles are on the same shaft in the peddle box - check box not loose or cracked or corroded

There's a bellows type thing on the clutch peddle cylinder ..this could make a squishy air sound.

other than that , these are the first things to check

look also for leaking brake fluid


all the best.mark

[andz327]

When switched off you should hear the last of the vacum getting used if you pump brake, if your not getting this then check vacum line from pump to brake servo, if it has air con there's a vacum hose that goes through the bulkhead near the heater hose and can perish and split causing vacum leak

Sent from my SM-G990B using Tapatalk

[MartinP86]

Thanks, i'll check the fluid level (but that was OK when i last checked) and i'll check the vacuum hose described, and get back to you

[MartinP86]

Been a while, but yes after i've driven for a while, i shut off the engine and when i then press the brake pedal a few times i can hear air.

Also, sometimes when i'm at a traffic stop for example, the engine will rev between about 900 and 1200rpm, then fall back to 900rpm and go back up to 1200rpm, etc. This usually goes away when i release the clutch pedal a bit and then press it again, figured it might be relevant to the issue. There's no engine codes on this, i've checked that again with Forscan and Delphi.

[metalworker0]

Think that is the anti stall kicking in .. increases revs to prevent stalling in traffic

put this into google you'll see the full AI description on how it works

"anti stall ford revs"

all the best.mark

[MartinP86]

I don't think that's the problem, unless the van can't acclerate at around 1200rpm 5 out of 10 times. Also when i shift from first to second and second to third gear for example it does this. If it is the anti stall there must be something wrong there. Pedal box related? Or could it be the electric throttle unit? Got no error codes so no clue on that.

Still doesn't explain the problem with the softer clutch and brake pedal though. I've checked the brake fluid level today but that's good and there's no air in the system.

What i meant about the traffic stop revving issue, if i start the engine and then get out of the van it sometimes does this revving from about 900rpm to 1200rpm. I can sometimes let it stop doing that by driving a bit forward or backwards. It revs up to 1200rpm, falls back to 900rpm, then revs to 1200rpm, falls back again, etc. I'll record it next time the van does it and i'll post it here.

[metalworker0]

i believe there is a switch on the clutch pedal .. i could be wrong .. this tells the pcm that the clutch is in and your about to change gear.

all the best.mark

[MartinP86]

i have had that switch replaced, not sure if it was an OEM part but i ended up switching back to the original switch because the problem remained.

[tranmx2]

The 2012 fuel electric/electronic system is not the same as the 2007.
The 2012 does not have the SCV.
The 2012 engine can be very difficult to control when in 1st at low rpm when power is needed due to the antistall or hill assist cutting in. Very problematic.
The 2012 when in reverse goes uphill with the power being applied by the vehicles electronics. Not a problem.
The 1996 A6 pulls at low rpm uphill in 1st or reverse - the steeper the hill to more power is applied - the driver has control. Not a problem.
The driver of the 2012 does not have control at low rpm when power is required to go uphill in 1st.
The 2012 moves forward a few meters then the engine rpm/power is reduced by the PCM. = a stall or semistall, the engine with too low rpm struggles up the incline which does no good to the engine.

There is one post on the forum where the poster considers - SCV or antistall.
viewtopic.php?f=5&t=182135

viewtopic.php?t=175844

Info' on google A1 seems to refer to a petrol engine and seems very much an overview/ generalization of how it works, regurgigated.

[MartinP86]

I've obviously used the search engien on the forum, but nothing really matched this issue.

I still need to have a close look at the pedal box, but using google i am not sure of where a vacuum hose should be attached to the pedal box as the softer pedal/power cut issue seems to have to do something with vacuum. I have been a car mechanic but this one, to me there's no logic to both these issues and what their relation to eachother should be. Unless there's an anti stall problem which drops vacuum on the clutch and brake pedal or something? It sounds weird to me.

[knobby1]

I've obviously used the search engien on the forum, but nothing really matched this issue.

I still need to have a close look at the pedal box, but using google i am not sure of where a vacuum hose should be attached to the pedal box as the softer pedal/power cut issue seems to have to do something with vacuum. I have been a car mechanic but this one, to me there's no logic to both these issues and what their relation to eachother should be. Unless there's an anti stall problem which drops vacuum on the clutch and brake pedal or something? It sounds weird to me.

There isn't any vacuum line attached to the pedal box or clutch/brake pedals. The only vacuum involved with the brakes is the line going to the booster/servo in the engine bay from the vacuum pump. If you have A/C, there's a vacuum line which "T's" off the servo line and goes through the bulkhead behind the dash and supplies one or two of the heater controls.

Lord Knobrot

[metalworker0]

was a guy here not so long back .. a week maybe .. he had trouble with the brakes binding and odd feel to pedal, it was the brake servo/ booster breather, you can see the lump of sponge around the shaft area in this picture ... note: this one is dirty and will probably fail soon.

all the best.mark

[MartinP86]

Yesterday while driving the van i've been paying a bit more attention than i've done before. What i've noticed is that when i give the engine 1500rpm (or more) before engaging the clutch (so to drive away), the pedal pressures are good as is the throttle response. Any less than 1500rpm and i get the soft pedals and the weak throttle response.

Vacuum pump on it's way out or something? 1500rpm seems a bit much to me, 12-1300rpm should be more than enough to drive off smoothly.

[tranmx2]

2007 Ford Transit 260S 2.2TDCI 63kW.
The RWD may not be the same as the FWD.
2012 RWD the vacumn pump is at the back of the exh camshaft - not easy to get at or get it off.
I can show images of it if you have RWD that is the same as the 2012.
There is a pipe from the vacumn pump that is divided one to the brake servo and one to inside the cab.