Ok so this seems to be a odd problem..
I just bought a 03 supercharged cavie and it seems to be running "off"
This doesn't happen all the time just sometimes...say I mat it in second or third the car wont accelerate smooth and steady. I dont know exactly how to explain it but it doesn't pull smooth....kinda accelerates and then stumbles and then accelerates and then stumbles.
Some days it seems fine and doesn't have any issue at all.
It also seems like its got less power lately. Now it could be me just getting used to it though..not sure lol.
I know I had a similar problem on my sportbike and it ended up being the fuel pump was going out. It worked well enough to deliver fuel for normal driving but not enough for high rpm needs....maybe the same sort of issue?
What is AFR? What kind of timing? Any KR?
P&P Tuning
420.5whp / 359.8wtq
Woops I guess I left that out..
I am running just the reflash, with stock pulley, no h/e, running 94 octane fuel.
The last time it did it last night the car was pretty cool, was about 5 deg Celsius out.
Unfortunately I haven't had a chance to install my wideband since I just got the car.
Could it maybe just be fuel that isnt the rating it says?
Spark plugs need changing/ gapped?
Of is the culprit the @!#$ty gm flash?
Oh and ill throw this out there. One day I was driving and all was fine...then went to go and it wouldnt go basically. Wouldnt accelerate past 2000 rpm was stumbling all the place and wouldnt boost. So I turned it off and then on and it was 100% back to normal.
[ion wrote: C2]throttle position sensor
check spark plugs
also, Below a 1/4 tank? Could have had the pump replaced and they didnt do the venturi correctly like my car.
or it could be low fuel pressure
or it could be knock
or other things. Need more data to diagnose.
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
Full tank,
I'll have to put a gauge on my rail and see if I can get pressure. Do you know the fitting to connect to the relief valve on the fuel line?
There was a thought I may have tps issues. I happen to have one I got from a guy so I'll throw it in and see if it helps
Just talked to the original owner and he says the plugs are the stock ones from 2003. So they were not changed when he did the charger.
The pump was also changed.... Will be changing to a racetronics soon.
how many miles on the car? maybe its time for a tune up. Fuel filter, plugs, air filter. this sounds like a spark plug issue to me.
Just talked to the guy again and he said he changed the plugs but left stock gap.....
Do we have a winner??!!
If so what should the gap be and should I change to a colder plug?
What plug is recommended?
im guessing tuning issues. thats way too many driveability problems for a simple supercharger install. if you have good fuel pressure and good spark then it has to be a tuning problem. decreasing the plug gap shouldnt be an issue will low boost so i doubt that will fix your problem. did you install a 2.5 bar map sensor? the gm flash is designed to work with the ss map sensor or an aftermarket 2.5 bar map sensor. if your using the original 1 bar map sensor it can confuse the ecm.
Nope it is all 100% new kit from pace. It's been on the car for 5 years. It has all the required things.
I'm going to say it's worn plugs and fuel filter needs a change. 5 years on a boosted car on a set of plugs they have to be worn out by now even at lower k.
Philly D wrote:Nope it is all 100% new kit from pace. It's been on the car for 5 years. It has all the required things.
I'm going to say it's worn plugs and fuel filter needs a change. 5 years on a boosted car on a set of plugs they have to be worn out by now even at lower k.
Did you say 5 years on 1 set of plugs? WTF? I replace mine yearly....
Yah but to be fair I just bought the car a couple weeks ago.
The guy before never really drove the car.
Mine did that turned out to be a wire with a bad connection on tps
z28guy(KGM BEOTCH)
Philly D wrote:Yah but to be fair I just bought the car a couple weeks ago.
The guy before never really drove the car.
now you know why he didnt drive it.....
people tell people what they want to hear to make a sale. you need to dig into this system and see exactly what it has. first rule: never trust anyone.....
well we both know the old owner of this car,he did not drive it because he had a company car,and his wife had another car which she used for the kids,So the cavy just did not get used..
But up untill this point the car was used as a daily driver,So in this case the seller could be trusted.
Exactly. I know the guy and I trust him. Everything was done correct and he never drove it due to why Jason said. It has been looked after. Hell I think he only drove it 1500 km in the last year.
Was not a dd at all.
Well as an update and to tell everyone what the problem was....
Plugs!!!!
Bought some NGK LTR6IX-11's made sure the gaps where the same and popped them in. Car runs much smoother and accelerates as it should smoothly to redline. Problem fixed!
Looking at the plugs I can see why it was running like crap, and had bad fuel mileage. Some had close to a .60" gap and corroded to hell. Dont even know how the car ran.
Us guys at NGK like these stories!!
Man those plugs have HUGE gaps!
Mr Newb wrote:Man those plugs have HUGE gaps!
Thats what mine come out looking like as well, the thin wire part of the electrode wears down and the gap opens right up, its the one thing I don't like about the plugs. I think my gap opened up form .032 to .04x over the 10k miles I put on them in 10 months. I do love the plating that NGK uses on the threads that does not require the use of anti-seize.
Middle plug looks like its running hot though, its whiter than the rest AND it looks like the electrode somehow worn stubbier than the other ones, slight surface melt maybe?
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
Leafy,
Clearly here you are talking about something that you don't fully understand. Let m enlighten you a little bit, Philly you can listen in since this is your car.
Leafy, for you to know why you got that amount of gap erosion in 10k we have to understand the ignition system fully. The L61 uses a wasted spark system that most people do not fully understand, I found this out especially at UTI in Dallas last week when I taught a few classes there. With a wasted spark system half of the plugs fire from the ground electrode to the center electrode and the other half fire from the center electrode to the ground electrode. With this type of system we have gap erosion occuring at a much faster rate, as opposed to a normal ignition system. This is why his cavalier uses a NGK Laser Platinum OE from the factory. This plug has platinum on the ground electrode and firing electrode, this is why we can offer a 100,000 mile plug for these applications, as platinum is a much denser harder metal. OE plug was a ILTR5C-11. So running a 1 step cooler plug would be ok, which he is. this will be ok up to about 10-12psi. Using a single precious metal plug is ok in this vehicle, such as the Iridium IX, however we need to be aware of the service interval as its not a oe style plug. Usually we would reccommend that the IX series would be good until 50K, however when used in this style ignition system is may be far less , especially when a blower is added. This is why we see the gap growing with the IX series, because the ground electrode is a std ground electrode which is the weaker metal, this is why the gap is so out of whack on half of the plugs. The middle plug wasn't running hot, as plugs do not produce heat, the plug has 2 functions, to ignite the air fuel mix and to extract heat from the combustion chamber. So in this case would would have said that there was too much heat left in the combustion process, however it actually looks like there may have been chemical intrusion here as you can see the taper seat of the plug is wet. A greyish ash color is actually normal. This is an Iridium plug, so for it to have " surface melt " that you are reffering to means that , well Iridium melts at about 4500 degrees, that didn't happen, usually we see this fro people using a ramp style gapper on the 0.06mm firewires, Philly did you use a coin style gapper?
I was under the impression that wasted spark sparked all the plugs both ways but the ones in non firing cylinders got the reversed polarity. And I say at least some of the increase in gap must be from electrode erosion, we are flowing current in a gap there will be a loss of material on the cathode, just like when you're welding the tungsten gets shorter. When I say a plug is running hot, I mean the cylinder its in is running hot, I typically consider a plug thats pure white as one in a hot cylinder that ones not bad but its still different than the 3 which is why it throws an alarm for me.
That chemical intrusion on the threads, what causes that? I also see that on my plugs and just chocked it up to manufacturing tolerance allowing carbon or oil or something through the threads but, mine doesnt get to the sealing surface of the seat.
And any suggestion on a plug that'll give us longer life in this application without breaking the bank?
1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by:
Kronos Performance
WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
Lol.... 2 things
1. Cathode? WTF thats a joke right??? lol
2. We have amny plugs that will work, plugs are a classic example of you get what you pay for. I hate it when people call with a built XXX-block with 13:5:1 static and a 400 shot of nitrous and flip out when I give them a 50 dollar plug, plugs are an investment just like a engine, pistons etc.... some people think that a plug is a plug.... not the case..
3. As far as a plug that would not break the bank, this will depend on the set up as I would typically ask a few questions to see what plug is suitable for the set up. If you would like to let me know your static compression ratio, boost level and fuel source with timing numbers I can see if we have a plug for it that will be a good fit. What is breaking the bank for you by the way... just to have a baseline... this is different for everyone.
