Sudden power loss below 3k RPM???

[rpg_dog]

So I was leaving work for lunch today and as I pulled onto the main road I went to accelerate and as I started boosting I lost nearly all power. It was cold today and I only let it warm up a minute or so before I started driving. I pulled off the road to check my intake fittings (a screw was left loose once or twice before and I had the exact same issue), to find none loose. I tried to rev it in nuetral and it struggled to get to 3000 RPM's, but once it did, it reved up fine. I head back to work and have the same problem. It now accelerates VERY SLOWLY until after 3000 RPM when it accelerates fine, I boost about 10 PSI (lower than normal) and drives ok. Once I hit any gear below 3000 RPM I loose power again. I just had a recent rebuild (1500 miles ago) where all gaskets and seals were replaced, I had a remanufactured head put in but the bottom end looked good so was left alone. The MAF is plugged in, all spark plugs look ok, no unusual white smoke, I don't see any coolant in the oil. It seems most likely to be a fuel deliver problem or the head gasket, but the head gasket is only only 1500 miles old and I can't find any coolant and gas mixing. If it were fuel, wouldn't the problem remain constant through all RPMs? Any better ideas??? No chance to do a compression test yet. I'm hoping for something simple I overlooked, but I may just have to take her to the shop this week I have NO time to fix this. Thanks in advance for any help. By the way, almost everything is stock, 2g exhaust manifold, 6 bolt motor, 92 GSX, auto tranny, 145K, K&N filter, and the guy who did the rebuild said it looked a pulley was aftermarket. I bought it 3 months ago and had a messed up head and a broken valve, so probably wasn't babied by the previos owner.

 

[myturbo]

So I was leaving work for lunch today and as I pulled onto the main road I went to accelerate and as I started boosting I lost nearly all power. It was cold today and I only let it warm up a minute or so before I started driving. I pulled off the road to check my intake fittings (a screw was left loose once or twice before and I had the exact same issue), to find none loose. I tried to rev it in nuetral and it struggled to get to 3000 RPM's, but once it did, it reved up fine. I head back to work and have the same problem. It now accelerates VERY SLOWLY until after 3000 RPM when it accelerates fine, I boost about 10 PSI (lower than normal) and drives ok. Once I hit any gear below 3000 RPM I loose power again. I just had a recent rebuild (1500 miles ago) where all gaskets and seals were replaced, I had a remanufactured head put in but the bottom end looked good so was left alone. The MAF is plugged in, all spark plugs look ok, no unusual white smoke, I don't see any coolant in the oil. It seems most likely to be a fuel deliver problem or the head gasket, but the head gasket is only only 1500 miles old and I can't find any coolant and gas mixing. If it were fuel, wouldn't the problem remain constant through all RPMs? Any better ideas??? No chance to do a compression test yet. I'm hoping for something simple I overlooked, but I may just have to take her to the shop this week I have NO time to fix this. Thanks in advance for any help. By the way, almost everything is stock, 2g exhaust manifold, 6 bolt motor, 92 GSX, auto tranny, 145K, K&N filter, and the guy who did the rebuild said it looked a pulley was aftermarket. I bought it 3 months ago and had a messed up head and a broken valve, so probably wasn't babied by the previos owner.

proably fuel filter and if its a alum underdrive pully take it off and put fluid or rubber filled pully on it just a heads up the solid crank oullys are pos !!!!!! / and not good for motors exspecially ones with ballance shaft

 

[rpg_dog]

I dropped the car off at the shop yesterday, the mechanic did a compression test and told me by phone that #1 cylinder was at 90psi, and the other three were worse... he was very vague. He said the plugs looked like it is running rich, and assumes the problem is in the head. He wont be able to get to it til next week and I find that unacceptable. I'm going to go pick up the car now and take it to another shop. I was hoping someone here may have experienced the same problem and could offer some advice.

 

[myturbo]

I dropped the car off at the shop yesterday, the mechanic did a compression test and told me by phone that #1 cylinder was at 90psi, and the other three were worse... he was very vague. He said the plugs looked like it is running rich, and assumes the problem is in the head. He wont be able to get to it til next week and I find that unacceptable. I'm going to go pick up the car now and take it to another shop. I was hoping someone here may have experienced the same problem and could offer some advice.

i wonder why no one else has responded maybe you should try posting this in the tech and every thing else it couldnt hurt TRY THE CAM ANGLE SENSOR JUST HAD A SIMILUR PROB 2 DAYS AGO i wish i had more to tell you YOU WOULD THINK OUT OF HUNDREDS OF THOUSONDS OF MEMBERS ONE OF THEM WOULD HAVE HAD THIS PROBLEM

 

[rpg_dog]

Ok so here's an update, I took the car to another shop and paid to have them look at it. He did a compression test 110, 0, 0, 110. He said it was loosing air from the exhaust, so sounds like the valves are broke. Is there any way that the # 2 & 3 cylinders would tap the valves because I didn't fully warm up the car??? I just had this MO*&%*) F@#&(0 head replaced and rebuilt 1500 miles ago!!!!!! I still have the old head and will salvage parts if necessary on Christmas since it's my only day off. I'll post whatever I find.

 

[myturbo]

Ok so here's an update, I took the car to another shop and paid to have them look at it. He did a compression test 110, 0, 0, 110. He said it was loosing air from the exhaust, so sounds like the valves are broke. Is there any way that the # 2 & 3 cylinders would tap the valves because I didn't fully warm up the car??? I just had this MO*&%*) F@#&(0 head replaced and rebuilt 1500 miles ago!!!!!! I still have the old head and will salvage parts if necessary on Christmas since it's my only day off. I'll post whatever I find.

might be a blown head gasket in between two cylinders also when you do so do a compression test yourself because both of them said diffrent compression #'s does the piston hit valve ????