Author Topic: Rocky - I have some more work coming your way! (Read 3877 times)

FUBAR · « **Reply #25 on:** July 26, 2006, 09:39:47 am »

Quoting: Roadkill

Play it safe, Mate, rip all that ECU rubbish out !!

Don't Listen... its just voices in you're head...

Giblets · « **Reply #26 on:** July 26, 2006, 02:07:43 pm »

Quoting: Roadkill

Play it safe, Mate, rip all that ECU rubbish out !!

I was waiting for that.

Maybe I just didn't hit the noisy bit hard enough with the hammer?

Roadkill · « **Reply #27 on:** July 26, 2006, 03:23:37 pm »

That's the spirit !

Bleedin' Computer crap !!!

HardRockCamaro · « **Reply #28 on:** July 26, 2006, 03:47:00 pm »

Quoting: Roadkill

Play it safe, Mate, rip all that ECU rubbish out !!

No Amish boy!!!

I'm guessing you have a fuel pressure problem, which could mean the pump or the regulator is on the knack. Best way to check is to hook up a fuel pressure gauge to the valve towards the rear of the passenger side fuel rail. Pressure should be around 42psi on a stock car and it should hold it, in fact, it should climb as the revs rise.
Rocky is selling those adjustable ones (I have mine set to 49psi) and they're cheap so you could swap that out (you do have to take the big TPI plenum off to get to it mind).
If it's the pump that's a load more work.

Or it could be the memory chip (prom) in the ecu that has become corrupt. Id you do replace that make sure you get one from the same year and engine size etc.

There isn't a lot else it can be really...

FUBAR · « **Reply #29 on:** July 26, 2006, 03:49:01 pm »

Quoting: HardRockCamaro

If it's the pump that's a load more work.

I have a reciept with my car from when Rocky changed mine (Before I owned it) changed it the proper way I might add!

55starchief · « **Reply #30 on:** July 26, 2006, 03:51:54 pm »

If it is the pump i would simply go with an aftermarket one msomethinh like an aeromotive and fit it outside the tank

http://www.aeromotiveinc.com/ldetail.php?prod=4&th=1

HardRockCamaro · « **Reply #31 on:** July 26, 2006, 05:29:18 pm »

Proper is important.
I don't agree with the slicing a hole in the top of the tank method.

Rocky · « **Reply #32 on:** July 26, 2006, 05:42:59 pm »

even with the system closed or open loop it still takes a signal from the oxygen sensor to the ECU if it needs it,it doesnt normally but it still could be the cause as they should be changed every 30k miles,Im leaning more towards the Fuel pressure reg now seeing the graphs,Doubt its the pump or ecu as it isnt the same symtoms.

HardRockCamaro · « **Reply #33 on:** July 26, 2006, 06:03:21 pm »

I doubt it's the ecu as well, corruption on the map above 4,000rpm or whatever is dubious.
I suspect fuel pressure as well, I still doubt the 02 sensor though.

55starchief · « **Reply #34 on:** July 27, 2006, 03:29:41 pm »

Have just PM'd goatman for any light he can shed on this for you mate. He works the partscounter at a GM dealership in Tx so he can ask the techs for their advice

Giblets · « **Reply #35 on:** July 28, 2006, 08:42:33 am »

Thanks again fellas.

Most of what you say is lost on me, but hopefully Rocky can come to a conclusion today!

ianjpage · « **Reply #36 on:** July 28, 2006, 09:24:18 am »

Giblets · « **Reply #37 on:** July 28, 2006, 11:53:57 am »

Well Rocky has spent the morning checking the Co2 levels and they are fine right across the rev range. if anything it's running rich, not lean.

Now he's checking the fuel lines for a blockage.

I can see this becoming a proper pain in the arse to diagnose.

ianjpage · « **Reply #38 on:** July 28, 2006, 12:32:37 pm »

Quoting: Giblets

Well Rocky has spent the morning checking the Co2 levels and they are fine right across the rev range. if anything it's running rich, not lean.

Now he's checking the fuel lines for a blockage.

I can see this becoming a proper pain in the arse to diagnose.

Yeah could be a long winded job to track down!

55starchief · « **Reply #39 on:** July 28, 2006, 12:35:09 pm »

Quoting: Giblets

Well Rocky has spent the morning checking the Co2 levels and they are fine right across the rev range. if anything it's running rich, not lean.

Now he's checking the fuel lines for a blockage.

I can see this becoming a proper pain in the arse to diagnose.

Dwain said it wouldnt be the o2 sensor but rocky was sure it was so i didnt bother. Dwain said it would throw a fault code and even if it was on its way out it wouldnt affect the fueling like that he also said it could be a weak pump or the fuel regulator bypass

HardRockCamaro · « **Reply #40 on:** July 28, 2006, 01:43:22 pm »

I'm still guessing fuel pressure, so pump or regulator.

Jamieg285 · « **Reply #41 on:** July 28, 2006, 01:43:53 pm »

Quoting: HardRockCamaro

I'm still guessing fuel pressure, so pump or regulator.

+1

Roadkill · « **Reply #42 on:** July 28, 2006, 03:24:32 pm »

Quoting: HardRockCamaro

I'm still guessing fuel pressure, so pump or regulator.

Yeah, my money's on that . . . . . . Merely because I don't understand all that O2 sensor rubbish.

Carb the B!tch !!!

Giblets · « **Reply #43 on:** July 28, 2006, 05:13:03 pm »

Rocky's been on it all day and has found nothing.

It's revving clean above 4000rpm and there is no misfiring at all.

Co2 readings are consistant and the fuel lines are fairly new and show no blockage. Also the plugs show no signs of lean running.

Basically, I'm beginning to wonder if I'm the victim of a dodgy diagnosis because she still drives perfect, even when pushed, and the power output was what I expected anyway.

Rocky will probably tell you more here, but after a chat with him, I'm thinking of just leaving it until the next Rolling Road and getting it re-tested.

Titsy · « **Reply #44 on:** July 28, 2006, 05:50:11 pm »

The problem is, the fueling may well be sufficiant under partial throttle, which is how Rocky would have tested it at different RPM's, but at wide-open-throttle, which is how it was tested on the dyno, it is taking a lot more air, and hence a lot more fuel.... That's where the fault will show itself.....

55starchief · « **Reply #45 on:** July 28, 2006, 05:58:22 pm »

Quoting: Titsy

The problem is, the fueling may well be sufficiant under partial throttle, which is how Rocky would have tested it at different RPM's, but at wide-open-throttle, which is how it was tested on the dyno, it is taking a lot more air, and hence a lot more fuel.... That's where the fault will show itself.....

Yup the only way to create the fault is to have the car under full load at WOT. You could try a long stretch of road but realisticaly its gonna be a chassis dyno mate

Pod · « **Reply #46 on:** July 28, 2006, 06:48:06 pm »

Quoting: 55starchief

You could try a long stretch of road

There's a 1/4 mile stretch of road I know of, available over the weekend.
You get a handy timing slip afterwards too.

Titsy · « **Reply #47 on:** July 29, 2006, 12:14:22 am »

Quoting: 55starchief

You could try a long stretch of road

Pretty hard to go flat out down the road with a gas analyser trailing out your exhaust.......

55starchief · « **Reply #48 on:** July 29, 2006, 09:04:20 am »

Quoting: Titsy

Pretty hard to go flat out down the road with a gas analyser trailing out your exhaust.......

Could use a very long piece of wire

Rocky · « **Reply #49 on:** July 29, 2006, 10:38:36 am »

Yep its one of them faults that needs to be accesed on a rolling road and dealt with straight away,I cant put it under the same conditions without having the rear wheels turning but you need someone who knows the engine well too,
If it was fuel pressure at that sort of RPM it should glitch and Rafe said he had taken it at speed and no sort of hesitation etc.
Unless its a intermitent fault, but if it run 5 times on the rolling road the guy would know this.