My van feels sluggish on a comparison run!

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callum
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My van feels sluggish on a comparison run!

Post by callum » Mon Oct 10, 2016 9:53 am

Hi folks,
I wad replacing some wood from my aunts conversion in her 96 2.5 diesel aft 2wd, which involved a quixk drive around the block.

It felt like it had quite a bit more pep from standstill compared to my 95 diesel aft 4wd.

So, is that just the difference between 2 and 4 wheel drive or is there something i can do to improve it? There is a slight hesitation, and i mean very slight, from foot on pedal to go with mine. Is this ATF check and top up territory? Would that help?

It was quite a sad moment as their van is a bit more neglected than mine (although theirs is much nicer!) So it feels likw i've wasted my time doing all the servicing! Haha!
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Re: My van feels sluggish on a comparison run!

Post by roosmith » Mon Oct 10, 2016 12:59 pm

I'm sure someone will be along to provide more accurate help however I was always impressed just how quick off the mark our 4wd was. I've always had auto's and my last company car was a 192bhp auto Insignia, which was so much slower off the mark than the Bongo (only to react, not to accelerate!). I was never left wanting in my 4wd.
Vivaro named Stewart however ex '96 4wd 2.5TD owner.
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BongoBongo123
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Re: My van feels sluggish on a comparison run!

Post by BongoBongo123 » Mon Oct 10, 2016 2:13 pm

Guesses/pointers unless there is an actual problem with your engine/fuel system.

Tyre pressures, EGR valve blanked or not, premium diesel being used or not, tyre sizes (could change gearing), water tanks full/empty, interior weight differences, AFT non AFT roof ?, mileage, your driving style has worn the engine out prematurely over time, binding brakes, servicing quality and interval, check oil levels/filter, check your air filter. Yes you should definitely check your ATF fluid from time to time.

Maybe you need to try something like BG244 (high power carbon/fuel system cleaning additive) as a clean up and some regular treatment like Millers.

Maybe your turbo is not working very well ? Any tell tale signs like excess smoke coming out the back of yours ?

I am no expert these are just basics.
Last edited by BongoBongo123 on Mon Oct 10, 2016 2:25 pm, edited 1 time in total.
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mikeonb4c
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Re: My van feels sluggish on a comparison run!

Post by mikeonb4c » Mon Oct 10, 2016 2:25 pm

Assuming weight of vehicles is similar, that both engines are achieving normal operating temps and that 4wd is not much less efficient in power transfer than 2wd, my first guess would be the turbo, though that's really only a guess. Something involving the autobox shift might also be a candidate for suspicion. Whats the mileage of the two engines?

Has yours had its air filter changed regularly, as thats a simple thing to check.
callum
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Re: My van feels sluggish on a comparison run!

Post by callum » Mon Oct 10, 2016 2:34 pm

Yes, my van...a run down.

It runs nicely, no smoke out the back at all.
I run Millers additive, only for the last 3 tanks though.
My engine has done less mileage (115k MILES), i've done the banjo, oil change twice in the year i've had it, stainless exhaust, air filter (k&n inside air box), fuel filter. Normal stuff really, but i have looked after it!
I have had no worries from the van at all in terms of speed, or noises, just this one comparison has had me confused.
Weight should be same, both have mid conversions.
My tyres are fine, running standard sizes and pumped up.

My ATF level was ok when i bought the van a year ago, but i must confess to not checking it since *slaps own hand*
Perhaps i'll have a look at that tomorrow afternoon and see what i can do.
Hopefully not turbo related, you scary people!
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BongoBongo123
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Re: My van feels sluggish on a comparison run!

Post by BongoBongo123 » Mon Oct 10, 2016 3:11 pm

That is my basics exhausted, so hope you get to the bottom of it Callum.
They call me light foot.
callum
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Re: My van feels sluggish on a comparison run!

Post by callum » Tue Oct 11, 2016 4:34 pm

Just checked gearbox fluid, slightly below the Low marker, so yes, not good!
Ia it specific oil to this gearbox or generic?
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cmm303
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Re: My van feels sluggish on a comparison run!

Post by cmm303 » Tue Oct 11, 2016 5:03 pm

callum wrote:Just checked gearbox fluid, slightly below the Low marker, so yes, not good!
Ia it specific oil to this gearbox or generic?
Dexron-III
Level needs to be checked with gearbox warmed up, engine running on the level, handbrake on, cycle through gears into P, then check level.
I have found getting the level right a bit of a faff! Easy to overfill etc etc.

Did you only feel that yours was less responsive off the blocks?
Does yours respond the same when doing say 50 mph when the torque converter is locked?
How about when you come to a hill, does yours want to change down sooner than your aunt's?
Chris with BertieB
'96 White unconverted AFT 2.5L Diesel 4WD
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Re: My van feels sluggish on a comparison run!

Post by Gasy » Tue Oct 11, 2016 5:13 pm

I'd give the banjo filter a real good clean out
I sprayed something through mine to really make sure it was clear
Check/replace fuel filter
Then take it for a Italian tune up
( Give it a thrash down the motor way using the HOLD button to get them revs up into the red )
And see if that makes a difference
Gas safe heating engineer / plumber if you need any advice just shout.
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Re: My van feels sluggish on a comparison run!

Post by Gasy » Tue Oct 11, 2016 5:15 pm

To clean my banjo I soaked it in injector cleaner ( the stuff you poor into the tank )
Then blasted it dry with a can of compressed air
Worked wonders
Gas safe heating engineer / plumber if you need any advice just shout.
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mikeonb4c
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Re: My van feels sluggish on a comparison run!

Post by mikeonb4c » Tue Oct 11, 2016 5:38 pm

I think (but wait to see if one of the techies on here agrees) that provided you mark its current position carefully, you could try altering the throttle position sensor to see if it makes gear changes more spritely. You might try the pump timing similarly. Before either of those, maybe it'd be worth seeing if there are turbo cleaning additives you could try. There's also the EGR system which could be investigated/blanked. And there's the turbo intercooler, which likes to have a good flow of air over it, so check no obstructions there.
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Re: My van feels sluggish on a comparison run!

Post by Gasy » Tue Oct 11, 2016 6:04 pm

We used to alter the waste gate on the defender turbo to get more power
Very simple to do from what I can remember

Any one tried this on a bongo ?
Gas safe heating engineer / plumber if you need any advice just shout.
callum
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Re: My van feels sluggish on a comparison run!

Post by callum » Tue Oct 11, 2016 6:35 pm

Banjo is clear and the fuel filter was done in January, so that should be ok.
Tempted to look at the modifications, but not yet!
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cmm303
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Re: My van feels sluggish on a comparison run!

Post by cmm303 » Tue Oct 11, 2016 8:03 pm

callum wrote:Banjo is clear and the fuel filter was done in January, so that should be ok.
Tempted to look at the modifications, but not yet!
Could also step through some quick visuals initially.
Fuel pump for leaks - run your hand underneath and round the back.
Turbo for leaks and whistles.
Exhaust manifold leaking - missing or loose no. 1 stud, blackening around the tree of hoses behind alternator
Chris with BertieB
'96 White unconverted AFT 2.5L Diesel 4WD
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Re: My van feels sluggish on a comparison run!

Post by Bongolia » Tue Oct 11, 2016 10:58 pm

Hey Callum.
At the weekend I took the inter-cooler off the Bongo and found it quite heavily choked. May be worth popping the pipe off and having a looks on yours.
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