Stilll Running rich!
- Thread starter bigal0043
- Start date
would a bad isc cause bad gas millege as well???i also pulled the efi fuse and checked for codes again and nothing.. the light does work it was flashing steady when i checked for codes
Also i have no way of checking timing
Also i have no way of checking timing
btw i do hear a click click click when i stop the car.. that would mean my isc is working correctly?
I must have a vacum leak somewhere...
I must have a vacum leak somewhere...
JustAnotherVictim
Supramania Contributor
yeah,the isc is like stepping motor. the clicking means it should be working alright. dam,good luck on finding the leak,its usualy something stupid
Alright well i just filled up again and im getting about 17mpg give or take.... This is highway driving btw with hardly any boosting at all...
Is this good or bad?
Is this good or bad?
so it must be running rich under boost then correct... Because when i do my friend says he smells me and i get really bad gas millege....
vacum leak then?
vacum leak then?
Looking through this and back through your original thread, have you checked the clamps on your IC pipes since you installed them? I noticed mine were a little loose for comfort after a few weeks--you may have one (or many) just loose enough to cause leaks under pressure.
Also, pull off that bosch bpv and see if it holds pressure; a leaky bypass valve will exhibit symptoms of a boost leak, causing metered air to escape.
It sounds like it could be a boost leak that's causing your problems. I boost a fair amount (my car's only boosting 8psi though) and I typically get 22-23 mpg. 17 mpg is a good number; many users on the boards here report much worse mileage with their modified cars--however, 100 miles to a tank is like 6 mpg...
I'd recheck every IC hose clamp on the car, and also check that bosch bpv. Also, check the IC itself for leaks caused by physical damage (rocks, road debris, etc).
Good luck!
EDIT:
I had a slight "aha!" moment, and was going to say something about this, but logically it shouldn't be a problem. Exhaust gas escaping near the O2 sensor may cause a problem, but not what you're experiencing. The biggest issue would be if outside air was somehow introduced--this may cause the O2 sensor to read a false lean condition and introduce more fuel. Since you mention this happens most under boost, it would seem this couldn't be possible, as exhaust flow exiting the turbo and backpressure from the exhaust system would pressurize the exhaust enough to disallow any air introduction through this bad seal. Please please PLEASE correct me anyone if I'm wrong--but that's how I see it.
Also, pull off that bosch bpv and see if it holds pressure; a leaky bypass valve will exhibit symptoms of a boost leak, causing metered air to escape.
It sounds like it could be a boost leak that's causing your problems. I boost a fair amount (my car's only boosting 8psi though) and I typically get 22-23 mpg. 17 mpg is a good number; many users on the boards here report much worse mileage with their modified cars--however, 100 miles to a tank is like 6 mpg...
I'd recheck every IC hose clamp on the car, and also check that bosch bpv. Also, check the IC itself for leaks caused by physical damage (rocks, road debris, etc).
Good luck!
EDIT:
bigal0043 said:
I had a slight "aha!" moment, and was going to say something about this, but logically it shouldn't be a problem. Exhaust gas escaping near the O2 sensor may cause a problem, but not what you're experiencing. The biggest issue would be if outside air was somehow introduced--this may cause the O2 sensor to read a false lean condition and introduce more fuel. Since you mention this happens most under boost, it would seem this couldn't be possible, as exhaust flow exiting the turbo and backpressure from the exhaust system would pressurize the exhaust enough to disallow any air introduction through this bad seal. Please please PLEASE correct me anyone if I'm wrong--but that's how I see it.
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how do you check a bpv again??? i will check my clamps and look at the ic for leaks as well... oh and the 100 miles to the tank thing was how long i did my testing the first time to see how many mpg i was getting.. My gas gauge acts up sometimes so i usually fill up around 100- 150 miles.. Usually around 6-7 gallons to fill it give or take a gallon
A simple way to check the valve is to pull it off and see if you can blow through from either side. Also, if you can get your hands on a vacuum pump, pull a few inches of mercury at the vacuum port on the bpv and see if it holds it for a minute. Ideally you'd want some way to check the valve itself with 10-13 psi, but that would require fabbing up a pressure tester.
Personally I had problems when I ran bosch bpvs, but I may have been a weird case. The diaphragms kept ripping on me; went through 2 in a one-year period of time. As far as I knew from my AutoMeter boost gauge, I never ran more than 11 psi.
Personally I had problems when I ran bosch bpvs, but I may have been a weird case. The diaphragms kept ripping on me; went through 2 in a one-year period of time. As far as I knew from my AutoMeter boost gauge, I never ran more than 11 psi.
okay so those two places for a vacum hook up on top of the engine on the valve covers...would a hole in one of those cause a rich problem? they seem kinda ratty
How does the car idle/run when cold? Have you checked your temp. sensor (in the thermostat housing)? I'm thinking cold start injector. I don't know if the ecu throws codes for this.
nope cleaned the csi last year sometime... was having trouble starting when cold but after i cleaned it works fine.. idles around 1200 when cold give or take
in the tsrm it stated to check the plugs i mentioned... ill go back and check the ks with what other plug?
btw i have no cat
also got a new multimeter.. its nothing spectacular but its better than nothing
btw i have no cat
also got a new multimeter.. its nothing spectacular but its better than nothing
jetjock, great info there. I should have merely put forth the question and let someone who knew what's what follow through with some solid facts. Next time I'll make better use of research and scientific fact instead of flailing about with "common" logic.
The first thing I thought of when I re-read "slight leak on my turbo elbow" was how older cars with exhaust leaks sometimes tend to backfire from ignition of the unburned fuel, which I thought was caused by the heated, unburned fuel in the hot exhaust manifold/exhaust system mixing with enough atmospheric air through diffusion (thanks jetjock) to create conditions favorable for autoignition.
So, in conclusion, to take a line from jetjock:
The first thing I thought of when I re-read "slight leak on my turbo elbow" was how older cars with exhaust leaks sometimes tend to backfire from ignition of the unburned fuel, which I thought was caused by the heated, unburned fuel in the hot exhaust manifold/exhaust system mixing with enough atmospheric air through diffusion (thanks jetjock) to create conditions favorable for autoignition.
So, in conclusion, to take a line from jetjock:
jetjock said:
didnt read thru everything so sorry if i am being redundant. did you check and adjust timing by the book
dont have a timing light.. but shouldnt i get a code for timing being off.. like 51 or something like that..(dont remember exact code)