Crappy GQ 4.2 Diesels..............

Submitted: Wednesday, Oct 27, 2004 at 21:26

ThreadID: 17369 Views:2927 Replies:9 FollowUps:6

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Voxson (Adelaide)

As bizzare as this sounds here is the story.............
I used to run 33x12.5 A/T's for a year and the car had heaps of power (well as much as you can have without a turbo),,, so i was pretty happy.... Changed oil filters with the oil every 5000kms, fuel and air filters every 10,000kms............

The other week i bought a set of Cooper S/T's in the exact same size and then the next thing i find out is that i have appeared to have lost about ½ my horsepower,,, maybe not ½ but at least quarter.....

It used to pull like a schoolboy with his first womens weekly magazine but since the tyre fitment the power has vanished... Can a more agressive tread pattern cause this???????

There is little black smoke,, all-tho i think the fuel econ has gotten worse... 15litres per 100 now,,, used to be as good as 13....

Have changed the oil and air filters recently and no change.....

Can injectors pack in as quick as this???????? or a coincidence fuel pump problem??????

Any good places in Adelaide to go and see without the usual $1000 entrance fee????

Regards Grant......

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Reply By: Utemad - Wednesday, Oct 27, 2004 at 21:34

Wednesday, Oct 27, 2004 at 21:34

Not all brands 33s are the same diameter. Perhaps your last ones were more like 32s and the Coopers are more like 34s?

Possible.

AnswerID: 82003

Reply By: Vinnie - Wednesday, Oct 27, 2004 at 22:02

Wednesday, Oct 27, 2004 at 22:02

PHEW!!! Lucky for me I own a Ford Maverick TD42 and not a "Crappy GQ 4.2 Diesel"

AnswerID: 82013

Reply By: Member- Peter & Mrs Peter, Lez - Wednesday, Oct 27, 2004 at 22:08

Wednesday, Oct 27, 2004 at 22:08

Noticed the same thing when I changed from 235/85/16 AT, to 235/85/16 MT.
Coming up the hill heading south on the Southern Expressway with the MT"s is about 15kmh slower than the AT"s. Can only put it down to different diameter tyre.
Cheers Peter

AnswerID: 82015

Follow Up By: Voxson (Adelaide) - Thursday, Oct 28, 2004 at 07:28

Thursday, Oct 28, 2004 at 07:28

Gday...I am glad to see someone else has had the same thing....
Do you think because the tread blocks are moving around more than A/T's???
The dia's are exact compared to my other tyres....Always run 40psi...

FollowupID: 341184

Follow Up By: Member- Peter & Mrs Peter, Lez - Thursday, Oct 28, 2004 at 20:17

Thursday, Oct 28, 2004 at 20:17

Could be, you can feel them "squirm" when taking a bend a little fast.

FollowupID: 341273

Reply By: Trevor - Thursday, Oct 28, 2004 at 02:09

Thursday, Oct 28, 2004 at 02:09

Grant,
Try
Len's Auto Repairs
165 Smart Rd St Agnes 5097
(08) 8396 3479

Len is a Nissan trained mechanic and owns a Patrol.

His work is first class and his prices are very reasonable.

Cheers,
trev

AnswerID: 82030

Reply By: Wayne (NSW) - Thursday, Oct 28, 2004 at 06:16

Thursday, Oct 28, 2004 at 06:16

Grant,
Have you checked the tyre pressure. If the new set of tyres are low that would cause more drag. Failing that keep the tyres and buy a Toyota.

Wayne

AnswerID: 82031

Follow Up By: Member - Jeff M (WA) - Thursday, Oct 28, 2004 at 17:17

Thursday, Oct 28, 2004 at 17:17

LOL good one Wayne!
But yeah it sounds like tyre pressure, I know you say you run at 40, but maybe re check as when by desert dullars are running low it feels like I'm towing a caravan! :-P

FollowupID: 341248

Reply By: Lone Wolf - Thursday, Oct 28, 2004 at 07:04

Thursday, Oct 28, 2004 at 07:04

May have to swap Womens Weekly with Cleo....

AnswerID: 82033

Follow Up By: bushfix - Thursday, Oct 28, 2004 at 08:14

Thursday, Oct 28, 2004 at 08:14

oh I'll pay that one! excellent lateral thinking!

FollowupID: 341186

Follow Up By: Des Lexic - Thursday, Oct 28, 2004 at 10:39

Thursday, Oct 28, 2004 at 10:39

Are you changing to Cleo because the Women's Weekly is now Monthly

FollowupID: 341198

Reply By: Truckster (Vic) - Thursday, Oct 28, 2004 at 10:21

Thursday, Oct 28, 2004 at 10:21

1) black round rim protector pressures

2) swap wheels with someone else with AT's of same size again go for a drive and see if it is just coincidence...

3) Yes injectors can be killed by 1 bad tank of diesel. You could try some Nulon injector cleaner - it wont do any harm...

4) Hiflo in melbourne do exchange injectors...

AnswerID: 82054

Follow Up By: Member - Jeff M (WA) - Thursday, Oct 28, 2004 at 17:20

Thursday, Oct 28, 2004 at 17:20

I'll actually give a bit of a rap to Nulon diesel injector cleaner. The surf's not doing many k's at the moment, it's sitting in the garage and only get's a run every other week. (we are waiting for the bub!) :-)
I noticed it getting a little smokier than usual, whack some nulon in and by the next tank she was as good as gold. Not only that, but it's about $10 a bottle and'll do 100L's so for me that's nearly two tanks! (I know it's sad, I need a long range!)

FollowupID: 341249

Reply By: michael - Thursday, Oct 28, 2004 at 11:37

Thursday, Oct 28, 2004 at 11:37

Grant, don't panic. When I had turbo fitted, Steve Boyle from United Fuel Injection did mention the BFG A/T 23/85/R16 LT'S on our Mav TD42 sapped more power on the dyno than other more street oriented styles. From my cycle racing experience this makes perfect sense. It is obvious once you become the engine! Heavier tyre as in mine with LT thicker sidewalls must be slower than highway style. A trade off I live with.
Cheers DRC

AnswerID: 82061