Intermittent Hesitation - Any Ideas What's Causing It?

[blue monster]

Evening all,

Since purchasing our T180 we have experienced intermittent hesitation/flat spot around 1500-2000 rpm and initially thought it was a trait of the car as such. Anyway, I read up on chip kits and they suggest that they eliminate flat spots in addition to more power, so I bought one and have had huge fun with the RAV over the last 2 months since it has been fitted and have seen a good increase in MPG. As some of you will be aware I have experienced limp mode a few times over the last few weeks and seen the good old check VSC, engine management, check 4x4, so our chip kit was replaced which resolved the problem but we still have this random hesitation.

I had the car back in to Mr. T today and they have been unable to find any thing wrong but suggested that it was the chip kit again and to run it for a few weeks with the kit disconnected, however, I am not convinced that it is the chip kit as this hesitation was there before we bought the kit and now that we have got used to the extra power and extra MPG I don't really want to give it up!!

Tonight I took the EGR valve off to inspect that and expected it to be the root cause of the problem but it was very clean and doesn't come as any surprise as the previous owner had always run it on V-Power and so do I.

So I am at a loss as the hesitation is very sporadic and as soon as you put your foot down it clears.

Has any one got any ideas as to what is causing this or experienced this as I am getting a little pee'd off and poor old Andy on the service desk at Lindops got an earful tonight after me having a !Removed! day in work - so Andy if you read this forum - my apologies , as I said earlier I was not venting at you personally - just venting my frustration based upon the fact that I did not expect this from a motor that I paid £17.5k for a few months ago.

[blitzchaser]

Hi put a can of bg244 in a full tank of diesel when you reach quarter full fill tank up again you will notice the difference..... going into limp mode is got to do with your chip.. i have a chip on my d4d van nearly 3 yearsnever went into limp mode...

[blue monster]

Already used bg 244 & like I stated chip kit has been replaced which seems ok now, just this slight hesitation

[anchorman]

Take that EGR off and with a pair of long nose pliers, open the valve and let it spring shut. It should do so with a real metallic ping. If it doesn't, take the motor off (after scribing a mark for refitting) and clean any traces of carbon from under the seat.

After that, change the fuel filter.

[blue monster]

At the advice of Kingo, we are going to run it for a few weeks without the chip kit connected and track/record how many times we experience this flat spot/hesitation.

As far as taking the motor off the EGR valve I would be afriad of refitting it incorrectly - if that is possible :o

Also, I am more than happy to try a new fuel filter in a few weeks time once we establish that it is not the chip kit at fault - which I am certain of as we would have to be very unlucky to have experienced 3 faulty chip kits in the space of a few months and the fact that no one else's kit has failed.

[Mistermena]

The 1st thing I would do is change that fuel filter again as Anch's has said. But I can understand why you're not doing that at this point. Sounds like it could be a faulty EGR valve to me to. But that would have surely come up with a fault code when the car was at Mr T's wouldn't it? Not sure...

I hope you get to the bottom of it mate as I know how frustrating it can be when you try to look after the motor using BG244 and V-Power derv ect. Fingers crossed for you

[freestyle]

hi blue,

does it happen on pull away, like in this thread?

[blue monster]

No, it is fine when we pull away, it is more like I said in the original post, around the 1500-2000rpm it is noticeable when in traffic or turning off a roundabout where you have to back off the throttle for a split second, back on & then there is this flat spot/hesitation.