Crazy gas milage and high rpm hesitations
#26
Full Member
Thread Starter
Everything was closed, lights and radio were off. No matter what I try I can't get the idle speed below 850.
By the way I forgot to mention that I removed the spark plugs today and found signs for the car running damn rich. The upper pulgs were black with a thick layer of carbon. The lower ones were completely brown. More like what I'd await to see at the upper plugs.
By the way I forgot to mention that I removed the spark plugs today and found signs for the car running damn rich. The upper pulgs were black with a thick layer of carbon. The lower ones were completely brown. More like what I'd await to see at the upper plugs.
#27
Moderator
iTrader: (1)
Everything was closed, lights and radio were off. No matter what I try I can't get the idle speed below 850.
By the way I forgot to mention that I removed the spark plugs today and found signs for the car running damn rich. The upper pulgs were black with a thick layer of carbon. The lower ones were completely brown. More like what I'd await to see at the upper plugs.
By the way I forgot to mention that I removed the spark plugs today and found signs for the car running damn rich. The upper pulgs were black with a thick layer of carbon. The lower ones were completely brown. More like what I'd await to see at the upper plugs.
Since the upper plugs are trailing then you might want to replace those or just clean them off and see what good it does if any.
#28
Full Member
Thread Starter
I allready cleaned them. No difference. I'm going to try the idle thing tomorrow again.
If one of the coils is damaged, which one would it be to cause those hesitations?
By the way I'm going to have a closer look at the groundings again tomorrow. Should I try to ground the air flow sensor directly at the connector maybe or would that be a bad idea?
If one of the coils is damaged, which one would it be to cause those hesitations?
By the way I'm going to have a closer look at the groundings again tomorrow. Should I try to ground the air flow sensor directly at the connector maybe or would that be a bad idea?
Last edited by Th0m4s; 11-30-11 at 01:37 PM.
#29
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iTrader: (1)
I would go ahead and disconnect the trailing and see if it behaves the same exact way or not.
Depends on whether you're confident that the grounds are good as is. The ground wire at the AFM feeds 4 other sensors so if one is good then they "should" all be good. If you do add a ground to the sensor then ground the other end to the engine such as at the thermostat housing.
Depends on whether you're confident that the grounds are good as is. The ground wire at the AFM feeds 4 other sensors so if one is good then they "should" all be good. If you do add a ground to the sensor then ground the other end to the engine such as at the thermostat housing.
#30
Full Member
Thread Starter
Going to disconnect the coil tomorrow then. Something is wrong with the grounding. I'm going to fix that, too. By the way: which sensor is the third? Pressure sensor, airflow sensor and which one else?
Last edited by Th0m4s; 11-30-11 at 02:22 PM.
#32
Full Member
Thread Starter
I finally managed to find the reason for those high rpm hesitations. Sounds totally stupid but it was a broken rpm gauge. I changed it today because sometimes it got stuck and was beeping all the time then. With the new gauge electronic my hestations are gone, too. I still can't explain why but i think it was producing some weird fuel cuts somehow.
I only got one other problem now. I can't adjust the idle speed. I tried it today again with bridged initial set coupler and unplugged BAC. The engine was idling at 400 rpm and no matter what I tried I wasn't able to get it any higher. I also tried it with plugged in BAC but got the same results. What the hell could have happened here?
I only got one other problem now. I can't adjust the idle speed. I tried it today again with bridged initial set coupler and unplugged BAC. The engine was idling at 400 rpm and no matter what I tried I wasn't able to get it any higher. I also tried it with plugged in BAC but got the same results. What the hell could have happened here?
#33
Moderator
iTrader: (1)
I finally managed to find the reason for those high rpm hesitations. Sounds totally stupid but it was a broken rpm gauge. I changed it today because sometimes it got stuck and was beeping all the time then. With the new gauge electronic my hestations are gone, too. I still can't explain why but i think it was producing some weird fuel cuts somehow.
I only got one other problem now. I can't adjust the idle speed. I tried it today again with bridged initial set coupler and unplugged BAC. The engine was idling at 400 rpm and no matter what I tried I wasn't able to get it any higher. I also tried it with plugged in BAC but got the same results. What the hell could have happened here?
I only got one other problem now. I can't adjust the idle speed. I tried it today again with bridged initial set coupler and unplugged BAC. The engine was idling at 400 rpm and no matter what I tried I wasn't able to get it any higher. I also tried it with plugged in BAC but got the same results. What the hell could have happened here?
#34
Full Member
Thread Starter
No no the engine was idling at 850 and I wanted to adjust it a bit so I grounded the initial set coupler. After doing that the idle speed immediately went down to 400 and I wasn't able to get it up to 750 by turning the idle adjust screw. In fact I wasn't even able to get it above 450 even when I turned the screw out nearly completely.
When I removed the bridge form the initial set coupler the idle went back to 850.
When I removed the bridge form the initial set coupler the idle went back to 850.
#36
Moderator
iTrader: (1)
No no the engine was idling at 850 and I wanted to adjust it a bit so I grounded the initial set coupler. After doing that the idle speed immediately went down to 400 and I wasn't able to get it up to 750 by turning the idle adjust screw. In fact I wasn't even able to get it above 450 even when I turned the screw out nearly completely.
When I removed the bridge form the initial set coupler the idle went back to 850.
When I removed the bridge form the initial set coupler the idle went back to 850.
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