Knock Sensor?

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Louis Zerr
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Okay, I can't win with this friggen thing.

The car feels like it is bogging/surging, not major but as I ease into the gas it seems to stutter, not mjaor mind you, just enough to barely feel. That is what usually happens.

Then there are times where it reacts like I hit the rev limiter. I have a ricer A/F gauge and it doesn't show a lean condition when this happens. I've been trying to force it into this mode and watch gauges and such. It happens between 3k-4k typically in 3rd gear, but I have gotten it to happen other times. If I push the gas pedal more it usually goes away, this really happens when I am just doing some "normal" driving.

What do you guys think? I have a suspicion that my knock sensor is working overtime.
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Steve@Tasca
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Is it still N/A or is the turbo on it now? Still have an EGR system? Any codes?
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Louis Zerr
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N/A, No EGR, No codes
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iminhell
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DVOM, check resistance of all the injectors. Should read the same across the board.

That mid 3 - 4k range is where knock is more prevalent. Also where spark ramps up fastest.

Unless you have a way to datalog, the disco light will do no good; you've no way to average the AFR. Best to ignore it altogether.


FWIW, dirty MAFS can cause load and thus spark to be off. Clean the MAFS and see what happens.
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Second the maf. A unmetered air leak or faulty maf will cuse it. A pluged cat wil due the same thng. It resricts flow of the air coming in so the maf wont read right. I have also seen weak fuel pumps cause this. My money is on the maf. 8)
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Louis Zerr
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I will give my maf a cleaning, I'm pretty sure it is not the cat though. Fuel pump isn't that old either.
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Louis Zerr
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And now it all don't make a F**K anyway. The car is blowing so much black smoke right now I'm not driving it. It clears up once I am up t speed, but those people that like to get right on my bumper at stop lights get a nice puff of oil in their faces. Any ideas on this one boys?

I may start taking offers on the car at this point, pisin me off.
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It its black that means rich. Oil smoke is blueish. Under load it burns rich. I think you have a mass air flow that shit the bed. With out a scan tool handy i cant see it. But i have a scan tool but your there and im here. Any way, there are two sensors in the maf a baro sensor and the air mass sensor. The maf should read between high 2.8 to 4.6-5.0 some wheres in thar. A rough guess is one gram per second per cylinder at idle at operating temp. The baro will mess with fuel trims where im at it should be around 155-52 . Also a injector check should be in order as if it is hanging open it will run rich. Most the time a maf wll cause a lean condition. Also your o2s can cause a rich condition mostly lean though. A easy way to inspect fuel injectors is pull the rail with jectors on it. Cycle the key on and watch for one to keep dribblin after the inital prime spray. This one is gonna require some intamate time with a scanner and a dvom 8)
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Louis Zerr
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focinite wrote:It its black that means rich. Oil smoke is blueish. Under load it burns rich. I think you have a mass air flow that shit the bed. With out a scan tool handy i cant see it. But i have a scan tool but your there and im here. Any way, there are two sensors in the maf a baro sensor and the air mass sensor. The maf should read between high 2.8 to 4.6-5.0 some wheres in thar. A rough guess is one gram per second per cylinder at idle at operating temp. The baro will mess with fuel trims where im at it should be around 155-52 . Also a injector check should be in order as if it is hanging open it will run rich. Most the time a maf wll cause a lean condition. Also your o2s can cause a rich condition mostly lean though. A easy way to inspect fuel injectors is pull the rail with jectors on it. Cycle the key on and watch for one to keep dribblin after the inital prime spray. This one is gonna require some intamate time with a scanner and a dvom 8)
First things first, I have a spare MAF. Gonna swap the guts and see what happens.

Thanks!

FYI, I haven't had time to clean it yet. My phone goes off way too often, working a 24/7 job sucks ass.
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I bet. I hate being needed nonstop for eight to tweleve hours a day. Lol . Try the maf if it dont clear up id look at fuel injectors. You dont want to drive it a whole lot as the rich condition will foul the cat.
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Louis Zerr
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focinite wrote:I bet. I hate being needed nonstop for eight to tweleve hours a day. Lol . Try the maf if it dont clear up id look at fuel injectors. You dont want to drive it a whole lot as the rich condition will foul the cat.
Let's just say I'm not too worried about the "cat".
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Steve@Tasca
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focinite wrote:I bet. I hate being needed nonstop for eight to tweleve hours a day. Lol . Try the maf if it dont clear up id look at fuel injectors. You dont want to drive it a whole lot as the rich condition will foul the cat.
Psst, hey Rob, he doesn't have a cat on the car
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FORDSVTPARTS wrote:
focinite wrote:I bet. I hate being needed nonstop for eight to tweleve hours a day. Lol . Try the maf if it dont clear up id look at fuel injectors. You dont want to drive it a whole lot as the rich condition will foul the cat.
Psst, hey Rob, he doesn't have a cat on the car
why are we whisperin? Yeah i didnt think of that. Oh well drive the ish out of it.
8)
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Louis Zerr
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Okay, I finally had a few to crack it open a bit. I ohm'd out the injectors and they seemed to be all the same within normal range. When I removed the harness I noticed a smell of fuel. At that point I removed the fuel rail. Inspected the O rings and noticed some really old crusty O rings that were probably leaking.

Do you think bad O rings could cause the issue? Vacuum leak/fuel leak?
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Steve@Tasca
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Anything is possible, replace them and find out.
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