Running so lean that the car wont hold idle , WTF!
08-14-06, 02:51 PM
#1
Running so lean that the car wont hold idle , WTF!
It all started last week. Finally finished all the little things on the TII swap into the vert. Took it out for a short drive and it ran great. Get to the gas station and the idle kind of sputters , blip the throttle and its back to normal. So whatever.. now the car sat for probably a year with the previous owner and about 8 months with me , so the gas in there is pretty ******* old. But the thing is the car fired right up with it so it seemed to be fine.
Anyway back to the gas station , filled it up with nice and sexy 93 , probably like 30 dollars worth. Hop in the car and start driving and it just ***** itself, doesent want to hold idle seems like its running on 1 rotor, has no power etc. That was fun , 6 puck unsprung , no ps and having to blip the throttle, nothing like working 3 pedals at the same time with 2 feet.
Barely get it home , looked like one of the secondary injectors was leaking so we fixed that still no go. Same thing 300rpm idle , shaking to peices , no power etc.
Thought I blew it , checked compression , its like 95-100psi on all surfaces. So wtf. Figured the injectors are clogged , swap the other set of 550s in , bang , car is back to normal , basically perfect idle at like 900rpm. But after it runs for a minute it starts to do the same sputter but still runs and its not as bad as it was before. Also if you give it gas it revs up but dies as you let go and the rpms drop.
Yesterday we wired in my safc and my wideband. My exhaust hasnt arrived yet so we just stuck the 02 bung into one of the exhaust pipes. Its running lean as **** as in off the chart , we dumped a shitload more fuel into it and got the idle to a 14.7 but it still pretty rough as in it dosent want to stay steady.
The car right now has rtek 1.7 , stock 550s , venom 720ccs , new fuel filter.
My guess is maybe the gas tank was really dirty and thus it clogged up the fuel filter and the previous 550s. Does that seem plausable? And would all that make the car lean out that much?
What I was pondering was to empty out the gas tank, disconnect all the lines , using a compressor blow them out , pop in another new fuel filter although like I said this one has like .5 miles on it.
As far as everything else goes , new plugs , new wires , new oil filter , emissions removed. One more thing I can think of is I dont have a TII afm , atleast I though I did but in the end the one I bought ended up being a NA. From what I've read though the car should still run fine.
Anyway , can anyone help me solve this issue? Thanks in advance.
Anyway back to the gas station , filled it up with nice and sexy 93 , probably like 30 dollars worth. Hop in the car and start driving and it just ***** itself, doesent want to hold idle seems like its running on 1 rotor, has no power etc. That was fun , 6 puck unsprung , no ps and having to blip the throttle, nothing like working 3 pedals at the same time with 2 feet.
Barely get it home , looked like one of the secondary injectors was leaking so we fixed that still no go. Same thing 300rpm idle , shaking to peices , no power etc.
Thought I blew it , checked compression , its like 95-100psi on all surfaces. So wtf. Figured the injectors are clogged , swap the other set of 550s in , bang , car is back to normal , basically perfect idle at like 900rpm. But after it runs for a minute it starts to do the same sputter but still runs and its not as bad as it was before. Also if you give it gas it revs up but dies as you let go and the rpms drop.
Yesterday we wired in my safc and my wideband. My exhaust hasnt arrived yet so we just stuck the 02 bung into one of the exhaust pipes. Its running lean as **** as in off the chart , we dumped a shitload more fuel into it and got the idle to a 14.7 but it still pretty rough as in it dosent want to stay steady.
The car right now has rtek 1.7 , stock 550s , venom 720ccs , new fuel filter.
My guess is maybe the gas tank was really dirty and thus it clogged up the fuel filter and the previous 550s. Does that seem plausable? And would all that make the car lean out that much?
What I was pondering was to empty out the gas tank, disconnect all the lines , using a compressor blow them out , pop in another new fuel filter although like I said this one has like .5 miles on it.
As far as everything else goes , new plugs , new wires , new oil filter , emissions removed. One more thing I can think of is I dont have a TII afm , atleast I though I did but in the end the one I bought ended up being a NA. From what I've read though the car should still run fine.
Anyway , can anyone help me solve this issue? Thanks in advance.
08-14-06, 08:22 PM
#2
Sorry I can't be much help but I can answer one thing. You should change your fuel filter regardless, even on mere suspicion. And yes, a clogged fuel filter could make you run very lean.
I could imagine 93 octane making things slightly worse. It's a little harder to burn and a little less energy dense, which usually doesn't matter. Not the cause of the problem but I'm saying it doesn't help either. It's just more knock protection.
I could imagine 93 octane making things slightly worse. It's a little harder to burn and a little less energy dense, which usually doesn't matter. Not the cause of the problem but I'm saying it doesn't help either. It's just more knock protection.
08-14-06, 10:59 PM
#3
Well changed the fuel filter again, spliced my fuel pressure gauge right in the line that runs from the fuel filter into the engine .
It reads like 50 at idle and from what I see it should be like 28-32 so yeah not sure what else it can be.
Maybe the walbro although its brand spanking new or maybe its my stock frp?
Anyone else care to offer suggestions?
It reads like 50 at idle and from what I see it should be like 28-32 so yeah not sure what else it can be.
Maybe the walbro although its brand spanking new or maybe its my stock frp?
Anyone else care to offer suggestions?
08-14-06, 11:15 PM
#4
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Warm the thing up. Then turn the Variable Resistor full clockwise and see if the afr and idle get any better.
Sure you don't have a primary/secondary injector plug in the wrong place?
Real lean could also be a air leak. Check the TID at the turbo for any cracks at all, usually under the clamp.
Don't have your hose from the intercooler to the Air Bypass Valve mis routed??? Can't be allowed to go from the intercooler directly to the nipple next to the bac. Not allowed. Either cap the intercooler feed or route it to the Air Bypass Valve.
Sounds like a air leak. Where and how? Got me. Too many things to look at. Large intercooler hoses need to be looked at also. BOV not connected?
On the back of the pipe that leaves the turbo outlet duct, there is a checkvalve, silver in color that somethimes does not get plugged in the duct and that causes a air leak.
Or the feed line for the bac from that turbo outlet duct has a loose clamp/cut/????
The brake booster vacuum feed line on good? The four nipples one above the other on the back of the thottle body all have hose on them or capped off to prevent leaks?
Upper intake manifold mating surface to the lower have a piece of wire? gasket holding it off the mating surface?
Have a turbo boost sensor in place of the n/a one? A must.
Used the n/a harness or the turbo one? IF the turbo one, did you rearrange the wiring at the FEM-01/FEM-02 plugs?
Sure you don't have a primary/secondary injector plug in the wrong place?
Real lean could also be a air leak. Check the TID at the turbo for any cracks at all, usually under the clamp.
Don't have your hose from the intercooler to the Air Bypass Valve mis routed??? Can't be allowed to go from the intercooler directly to the nipple next to the bac. Not allowed. Either cap the intercooler feed or route it to the Air Bypass Valve.
Sounds like a air leak. Where and how? Got me. Too many things to look at. Large intercooler hoses need to be looked at also. BOV not connected?
On the back of the pipe that leaves the turbo outlet duct, there is a checkvalve, silver in color that somethimes does not get plugged in the duct and that causes a air leak.
Or the feed line for the bac from that turbo outlet duct has a loose clamp/cut/????
The brake booster vacuum feed line on good? The four nipples one above the other on the back of the thottle body all have hose on them or capped off to prevent leaks?
Upper intake manifold mating surface to the lower have a piece of wire? gasket holding it off the mating surface?
Have a turbo boost sensor in place of the n/a one? A must.
Used the n/a harness or the turbo one? IF the turbo one, did you rearrange the wiring at the FEM-01/FEM-02 plugs?
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