Slow response

mr302xd · 29-06-2008, 06:51 PM

Hi all

Just wanted to know, my XR8 isnt as responsive as it should be i think, meaning when u give it a rev, its like a half a second or so response before u get suthin. Just wanted to know is this normal... and if not wat can i do to fix the problem...?

cheers Frank

**Stav** · 29-06-2008, 08:51 PM

The cars state of tune is out.Has it been serviced recently?

mr302xd · 29-06-2008, 08:57 PM

Quote:

Originally Posted by Stav

The cars state of tune is out.Has it been serviced recently?

Got serviced last week new plugs, leads, air and oil filter... but has been sorta slow since ive had it which has been bout a year.

JC · 29-06-2008, 09:27 PM

Could be stretched throttle cable.

chief · 29-06-2008, 09:30 PM

Was the fuel filter replaced during the service. Possibly fuel pressure regulator.

mr302xd · 29-06-2008, 09:48 PM

It doesnt feel like a throttle cable and filter wouldve been replaced around 15000k ago

b2tf · 29-06-2008, 09:51 PM

Was the air filter a K&N

**Stav** · 30-06-2008, 08:15 AM

The car will respond according to the power it has and state of tune.This will give the car a better response to throttle.Does the car go too lean on stomping the throttle? Does it go terribly rich? These have a tremendous effect on throttle response. I would also recomend you get your diff ratio looked at as well.

Sox · 30-06-2008, 10:44 AM

What are the condition of the cats?
And does it accelerate sluggish too, or is it just initial throttle response?

Rick.

V8 EF Fairmont · 30-06-2008, 05:26 PM

I've had this issue with both my EBII and EL V8 Fairmonts. Cleaning the MAF can make a huge difference, especially if you're running a K&N

mr302xd · 30-06-2008, 07:02 PM

no its not a K&n at the moment.

Cats are in good condition, just had em cheched out when i got my new exhaust.

It does accelerate a bit slugish, but my clutch is slipping a fair bit so that accounts for that.

When i give it a good rev out im getting a good wiff of petrol smell, could be running rich???

**Stav** · 30-06-2008, 07:55 PM

Check for fuel leaks mate!! Check the fuel filter connections first ,then all the lines to the front.From there ,make sure your injector o rings arent broken. If you have fuel distinctly from your exhaust then you have a misfiring cylinder which is not burning the fuel.

Edit: I really think its a fuel leak.

Sox · 30-06-2008, 07:59 PM

What's your fuel consumption like?

Rick.

mr302xd · 30-06-2008, 10:53 PM

out of a full tank i get prob 320k's

Sox · 01-07-2008, 07:29 AM

Quote:

Originally Posted by mr auxr8

out of a full tank i get prob 320k's

That's hideous consumption, even for an XR8. You should be getting somewhere between 400 and 600k's depending on driving conditions.

One of your sensors has gone bunk and it's running very rich, hence sluggish response and poor economy..
Probably best to wheel it into a workshop which can read the codes.

Rick.

james22 · 01-07-2008, 07:55 AM

My Xr at the best of times will get 350km around town, so I don't think its that bad lol

Sox · 01-07-2008, 08:17 AM

Quote:

Originally Posted by james22

My Xr at the best of times will get 350km around town, so I don't think its that bad lol

Is yours auto?
The OP's is manual, and 320k's is very poor, no matter where it's driven.

Rick.

james22 · 01-07-2008, 02:14 PM

Quote:

Originally Posted by Sox

Is yours auto?
The OP's is manual, and 320k's is very poor, no matter where it's driven.

Rick.

Mine is manual mate. and 350km is a good tank lol. Sounds like fairly average fuel consumption around town for the mods to me. My best friends stock AuII 200kw Xr, gets the same consumption as mine aswell. Albeit with a bit more right boot... :evil3:

But on average I get 350km around town driving normal, 400km if I take it easy, and easily 600 - 700km + on a nice flat bit of road with the cruise on for 6 hours straight. So too long story short, it sounds a little thirsty, but then again we did buy V8's for the fun didn't we

**Mont5.0** · 01-07-2008, 08:22 AM

i agree^^

RG · 01-07-2008, 08:50 AM

Pfft I'm lucky to get 250k around town in mine. 350-400 is normal I would think around town in an XR8 with 500-550 on the highway.

Sox · 01-07-2008, 08:57 AM

Quote:

Originally Posted by Russell

350-400 is normal I would think around town in an XR8 with 500-550 on the highway.

So you agree that the OP's 320k's is rather poor, as it's lower than your stated normal 350-400 around town.

Rick.

RG · 01-07-2008, 09:06 AM

Quote:

Originally Posted by Sox

So you agree that the OP's 320k's is rather poor, as it's lower than your stated normal 350-400 around town.

Rick.

320 in a stock to mildly modified XR8 is pretty poor. I'd be looking straight at the oxygen sensors on that especially with the smell of fuel he is getting.

Replace the oxy sensors, clean the MAF and throttle body. What leads and plugs did they use?

sly · 01-07-2008, 09:36 AM

If it were the oxy sensors he wouldn't smell unburnt fuel, it'd smell rich or sulphurous from the exhaust. The cats would process any excess fuel in the exhaust. If it's raw fuel he can smell there's a leak somewhere.

But just to hedge my bets, if he does have a U/S oxy sensor he'd best look at the cats again. Running rich for a while can wreck a cat real quick.

RG · 01-07-2008, 09:45 AM

Quote:

Originally Posted by sly

If it were the oxy sensors he wouldn't smell unburnt fuel, it'd smell rich or sulphurous from the exhaust. The cats would process any excess fuel in the exhaust. If it's raw fuel he can smell there's a leak somewhere.

But just to hedge my bets, if he does have a U/S oxy sensor he'd best look at the cats again. Running rich for a while can wreck a cat real quick.

I know mine runs rich at idle and I get a fuel smell occasionally. I also know that there isn't a leak and that my cats are fine. But in saying that I agree with you about the cats, it has all the call signs of a busted cat with the slow responsiveness and excessive fuel usage.

james22 · 01-07-2008, 02:21 PM

P. S - I get the above figures with a slow set of oxygen sensors, and AFR's running into the mid 10's (effin rich)

mr302xd · 02-07-2008, 11:22 PM

SO in summary wat should i do?? Check sensors?

The car seem to struggle when i put the foot down and you get a smell, pretty sure its fuel... possibly the smell of the clutch slipping loll

RG · 03-07-2008, 09:19 AM

Quote:

Originally Posted by mr auxr8

SO in summary wat should i do?? Check sensors?

The car seem to struggle when i put the foot down and you get a smell, pretty sure its fuel... possibly the smell of the clutch slipping loll

Get the clutch done, change the sensors, clean the MAF and clean the TB. Make sure they used the right plugs and leads. Check the cats too.

badashxr8 · 05-07-2008, 10:28 AM

wat kind of plugs and leads do ya suggest to use? for every 12l litres of fuel i get about 100km give or take depending if the foot gets planted plus mine is a manual.

RG · 05-07-2008, 05:15 PM

Quote:

Originally Posted by badashxr8

wat kind of plugs and leads do ya suggest to use? for every 12l litres of fuel i get about 100km give or take depending if the foot gets planted plus mine is a manual.

MSD leads from BOTTLEDUP and NGK plugs BPR6EFS-13.