Power loss 3K-4.5k - Ideas?
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Power loss 3K-4.5k - Ideas?
I have a 95 1.8, still N/A running stock ECU/spark/fuel.
I reinstalled the engine about a week ago and have been driving it around just a little bit. It is having some pretty noticeable hesitation between 3000 and 4500 RPMs. Before and after that rev range it pulls solid and normally, but feels starved in between.
I have a NBO2 gauge installed by the PO, and it reads fairly lean while it's lacking power. I don't know how much to believe a narrow band sensor though...
Before I pulled the engine for oil leak fixing (no more leaks by the way) it was running fine.
My first thought was timing, but I am seeing about 11*-12* btdc which I think is ok. My next thought is a fuel filter. I'll probably replace the fuel filter anyways, but thought it would be something else because it didn't hesitate before. It was only out of commission for about 3 weeks, and I put brand new gas in it as soon as it was back on the road.
Anyone else have any other ideas or things I should check? I'll also be replacing the plugs. They don't look too bad, but I don't know when they were replaced and they are cheap and easy.
I'm trying to get it running great before I install the MS and compound the difficulty in trouble shooting. Any help appreciated.
I reinstalled the engine about a week ago and have been driving it around just a little bit. It is having some pretty noticeable hesitation between 3000 and 4500 RPMs. Before and after that rev range it pulls solid and normally, but feels starved in between.
I have a NBO2 gauge installed by the PO, and it reads fairly lean while it's lacking power. I don't know how much to believe a narrow band sensor though...
Before I pulled the engine for oil leak fixing (no more leaks by the way) it was running fine.
My first thought was timing, but I am seeing about 11*-12* btdc which I think is ok. My next thought is a fuel filter. I'll probably replace the fuel filter anyways, but thought it would be something else because it didn't hesitate before. It was only out of commission for about 3 weeks, and I put brand new gas in it as soon as it was back on the road.
Anyone else have any other ideas or things I should check? I'll also be replacing the plugs. They don't look too bad, but I don't know when they were replaced and they are cheap and easy.
I'm trying to get it running great before I install the MS and compound the difficulty in trouble shooting. Any help appreciated.
Last edited by Cpt_Slow; 12-19-2008 at 04:19 PM. Reason: Noob grammar error
#2
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Here is a quick video clip of the tach and NBO2 gauge in 2nd gear at WOT. There's definitely a correlation between the O2 readings and loss of power. Every time the gauge dips to the lean side there is a noticeable loss in power. I would assume at WOT that the stock ECU would have that thing pegged on the rich side, but that's not what is happening.
Just before the video was shot I put in new NGKs and a fuel filter. I haven't tested the fuel pressure yet, but can't see why it would suddenly be low. If I can't find a solution really soon I'm just going to put in the 460 injectors, LC-1 and MS so I can at least better diagnose the issue.
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