Strange manners (tune related?)
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From: Hanover, Michigan
Strange manners (tune related?) My car acts kind of funny right now every once in a while.
Sometimes it has a dead spot in the powerband at around 2500-3000 rpm when I Give it about half throttle. It almost feels like my clutch isnt grabbing or something....but the revs dont go up....it just feels like it isnt pulling very good...and then about 2 seconds later it will kick in. IT doesnt back fire or miss...it just feels like the motor isnt pulling very strong.
This happens at about half throttle when slighty lugging a gear. For example If I was to be in 3rd gear at 45 mph and give it half throttle it would do this.
When cruising in 6th at 60mph the other day it also wanted to stall out when I would give it a quick 1/4 throttle stab.
I know the second part is tune related....but what about the first? I highly doubt it is the clutch because it will grab hard from a first gear roll and it will hold when lugging it hard.
Anyone else know what I am talking about? Anyone had this happen prior to a tune?...it almost feels like vtec or something.
I have until the 20th before I get the tune...do you guys think I am damaging my engine daily driving it on this kind of set-up? It is on a stock tune....but the svo injectors are not installed yet...so thats not the problem.
thanks, Troy
Sometimes it has a dead spot in the powerband at around 2500-3000 rpm when I Give it about half throttle. It almost feels like my clutch isnt grabbing or something....but the revs dont go up....it just feels like it isnt pulling very good...and then about 2 seconds later it will kick in. IT doesnt back fire or miss...it just feels like the motor isnt pulling very strong.
This happens at about half throttle when slighty lugging a gear. For example If I was to be in 3rd gear at 45 mph and give it half throttle it would do this.
When cruising in 6th at 60mph the other day it also wanted to stall out when I would give it a quick 1/4 throttle stab.
I know the second part is tune related....but what about the first? I highly doubt it is the clutch because it will grab hard from a first gear roll and it will hold when lugging it hard.
Anyone else know what I am talking about? Anyone had this happen prior to a tune?...it almost feels like vtec or something.
I have until the 20th before I get the tune...do you guys think I am damaging my engine daily driving it on this kind of set-up? It is on a stock tune....but the svo injectors are not installed yet...so thats not the problem.
thanks, Troy
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From: Hanover, Michigan
Did some more driving today. It seems to only happen in 3rd gear at just about 3100 rpm on the dot every single time. Reguardless of how much gas I give it....it does the same thing every time at this rpm in 3rd gear.
The motor will quit pulling for about 2 seconds...and by 3300-3400 rpm it will kick back in. The revs dont jump up high quickly...it almost feels like my clutch is halfway engaged or something.
Could this be a clutch engagement problem? I havent installed the adjustable master yet or the drill mod...I am having epp do that when I get the dyno tune...I wanted to have them set it up and get the clutch just right after the break in.
It almost feels like the clutch isnt grabbing because of some sort of engagement problem...but why only at this rpm? and how come it still grabs like hell if I floor it in first and second, and does not do this at all?
what the hell is going on....I am lost here
HELP HELP HELP
The motor will quit pulling for about 2 seconds...and by 3300-3400 rpm it will kick back in. The revs dont jump up high quickly...it almost feels like my clutch is halfway engaged or something.
Could this be a clutch engagement problem? I havent installed the adjustable master yet or the drill mod...I am having epp do that when I get the dyno tune...I wanted to have them set it up and get the clutch just right after the break in.
It almost feels like the clutch isnt grabbing because of some sort of engagement problem...but why only at this rpm? and how come it still grabs like hell if I floor it in first and second, and does not do this at all?
what the hell is going on....I am lost here
HELP HELP HELP
It sounds to me like you are getting into power enrichment possibly and the mixture is off. You may be rich or could very well be lean.
When I first installed my cam I had a horrible hesitation into P.E. The tune should cure it.
Dave
When I first installed my cam I had a horrible hesitation into P.E. The tune should cure it.
Dave
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From: Hanover, Michigan
I am hoping it is a problem with the stock tune with a bunch of mods. It just doesnt feel like one 
It doesnt stall out or backfire (unless in 6th like mentioned before) Just seems like it all of a sudden loses engagement.
If it was going lean or rich why would it happen at this same time every time? and not in other instances?
It doesnt stall out or backfire (unless in 6th like mentioned before) Just seems like it all of a sudden loses engagement.If it was going lean or rich why would it happen at this same time every time? and not in other instances?
It could possibly be when power enrichment is coming in. Power enrichment changes the AFR from 14.7 to 12.5 or whatever the stock setting is for PE. Your AFR mixture is off now with the camshaft install. So the cruising AFR may be 13.75 and PE will look for 12.5 for instance but it will skew way richer than 12.5. On the other side you may be 15.0 or leaner at cruising and it will look for 12.5 for PE and get only 13.4.
These are just numbers I have made up for an example. Simply put your AFR is off with the camshaft and driveability will suffer.
Dave
These are just numbers I have made up for an example. Simply put your AFR is off with the camshaft and driveability will suffer.
Dave
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From: Hanover, Michigan
Yeah I was thinking that as well. This car has never had a part failure of any kind in its history after 91k miles....so I guess it could be anything like that really....it is due you could say.
The main thing I am worried about is a clutch issue....but no one seems to think this is even a possibility...so I shouldnt even worry about that?
If it is not a clutch problem I am sure that EPP when dyno tuning will be able to tell what it is...hopefully just the stock tune acting up.
So...no possibility of a clutch issue?
thanks again
The main thing I am worried about is a clutch issue....but no one seems to think this is even a possibility...so I shouldnt even worry about that?
If it is not a clutch problem I am sure that EPP when dyno tuning will be able to tell what it is...hopefully just the stock tune acting up.
So...no possibility of a clutch issue?
thanks again