SR bogs, sputters?? No power

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duffman1278
Posts: 6816
Joined: Sun Apr 01, 2007 3:09 pm
Car: 89 240sx Hatch, the wildcats!

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Well I went out to drive my SR today after replacing my MAF, and now at idle I can rev the motor to redline easily.

However, when I went out to take a test drive, the car felt like it had NO acceleration, no power. So I checked for boost leaks and nothing. Checked my vacuum lines and they all seemed fine, their brand new lines.

So I went back out for another test drive and I found out that if I "pump" the throttle several times as I drive that it'll start to pick up and gain powe MUCH better and than boost kicks in around 4k. But I would have to do this everytime

Before this, even at full throttle it would not do anything, there was like little to no power. I tried adjusting the TPS, seems to read fine.

Any suggestions would be greatful


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DA82KC
Posts: 20
Joined: Thu Dec 27, 2007 6:40 pm
Car: 1982 Datsun King Cab 4X4 1983 Datsun Dual Cab 4x4, 1972 Datsun 1200 Coupe, 1976 Datsun 280Z

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Just curious, but what MAF did you put in and what does it go to? On the Sr20DET with stock ECU, they run most normally with the Single cam KA24E MAF or the OEM Sr20DET MAF. A DOHC KA24DE MAf will not work on an SR20DET, already tried and earned the merit badge!

duffman1278
Posts: 6816
Joined: Sun Apr 01, 2007 3:09 pm
Car: 89 240sx Hatch, the wildcats!

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I seemed to have fixed the issue, I took out the MAF, which is an SR20DET MAF, and I cleaned it with some MAF cleaner, than I hooked up my boost gauge and saw that my vacuum was running at 15Hg so I tightened up my idle screw since I know I loosened it, and the vacuum pressure started increasing. Now I can step on the gas an get good response. I also rechecked my TPS and set it to .35V according to FSM.

duffman1278
Posts: 6816
Joined: Sun Apr 01, 2007 3:09 pm
Car: 89 240sx Hatch, the wildcats!

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Alrite, I thought it was fixed, apparently not. I checked my boost gauge and it says my vacuum is at 15Hg, and shouldn't it be 18-20??

Well I can rev it easily to redline when I'm parked, but when I went out to go drive it, the car was the same, I had to pump the throttle for it to start getting some power. It was just so weak though before that. I held the throttle to the floor and NOTHING. I did notice though that when I pulled the coil out there was a small amount of oil coming out of the seals.

Could this cause a vacuum leak? I believe all 4 were leaking a bit.

grubby27777
Posts: 68
Joined: Tue Feb 20, 2007 3:14 pm
Car: s13 RB26, hatch with s14 sr

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i was wondering if you ever solved this problem?? i am having the same issue

duffman1278
Posts: 6816
Joined: Sun Apr 01, 2007 3:09 pm
Car: 89 240sx Hatch, the wildcats!

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Yea I solved it. I basically was flooding my second cylinder which meant I was getting no power since it couldn't burn it all. I bought another ECU, because I shorted out the other one, and badbing badda boom, fixed


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