Acceleration

[warrenpfo]

First off hello all from sunny SA it has been a while since i was last on but hopefully not forgotten.

My 80 has of late been having an acceleration conundrum.

On driving it hard (70/80 miles and hour for a few hours) or for extended periods of time (all day on a recent trip to the mountains in 4x4 and low range at time) the relationship between the acceleration pedal and engine response gets worse.

By this i mean i can put my foot down with very little or no response from the engine and then the delay is over and the engine will accelerate hard and take off. Once up to speed its fine but on occasion i have had to "manually"drop down the box to get it to wake up and go.

Its like the engine does not know to kick down when i put my foot down hard but even when put down gradually it still does not increase gradually in revs but rather gets to a point where my foot is almost flat and so the engine revs increase drastically.

Hope this makes sense and any advice??

 

[Gary Stockton]

Have the same sort of issue currently. Thought I had a slipping clutch but I now suspect a partially clogged fuel filter - which will be a pain as I put on a new one for our trip to France and then Morocco.

Suspect dirty fuel in Morocco somewhere possibly ...

 

[warrenpfo]

I had thought its either fuel or air but both filters are newish (last 9 months) but will check.

 

[Shayne]

The air intake has an expansion box so when you floor it the turbo can take a huge gulp of air and do its work , a restricted air filter will feel like turbo lag which fits the description .

 

[warrenpfo]

Its not air related i am sure of that. The air box is clean and un-restricted and the filter is clean. If anything it may be fuel related but i cant see how when i put my foot flat there is a delayed response from the engine. Its not like it struggles to increase in revs it just does not increase at all until a while later and by while we are talking 5 seconds

 

[joinerman]

Hi Warren, not going to help with an answer but mine had exactly the same symptoms when ever we had hot weather. Never got to the bottom of it.

 

[warrenpfo]

My thinking at present is engine/transmission gets warm, kick down cable heats up and expands and maybe there is too much slack in t to then react in line with the accelerator. I will check the cable for slack when next i take her for a long drive.

 

[AndyCook]

Welcome back !


Sent from my iPad using Tapatalk

 

[warrenpfo]

Never left but moving country takes it out of you and other things seem to take priority.

I just hope I can get to the bottom of my current problem

 

[Dave2000]

I would go with a fuel density problem as your problem appears to be heat related. If you start to experience the problem and knocked it in neutral would the engine rev immediately? If so ignore that can look at the transmission.

regards

Dave

 

[warrenpfo]

No idea Dave will check when next it happens

 

[warrenpfo]

So today i had driven not far but the engine was warm and I was driving along a flat parking lot and then came to an incline with a speed bump half way up. As the front wheels went over a put my foot down to gain the momentum i had lost braking to get the fron over and nothing happened. I remembered Dave's comment and knocked it into N from drive and the engine instantly shot up in revs.

 

[Dave2000]

What is the fluid level like in the transmission, does not sound engine related if you can rev the engine, but no drive.

regards

Dave

 

[warrenpfo]

Levels are good but fluid is old so want to change it as a first port of call. At the same time I have a new "kick down cable" so will replace and clean the strainer.

This can only be done in a few weeks time when we move into our new house.