yoshi280zx

Zed Head, Yes, it's a manual. Sorry - pretty important info. The problem is RPM specific - with the same results in every gear. Consequently, I'm in 5th by 40-45 MPH. It sucks... I bought the MSA throttle body years back for better performance. This upgrade was coupled with a MSA intake, K&N, ported intake manifold and new exhaust system. The car definitely breathes better and sounds great. I scrapped the old fuel rail earlier this year to go with one I made. A new FPR seemed logical. I grabbed a rising-rate Aeromotive unit. I didn't change the system's displacement, just the way the fuel was fed. It seemed better to have it go straight to the injectors instead of traveling above the manifolds forever... The car has run fine with all the upgrades. This just started happening out of nowhere - no recent mods... I think it's the TPS. There was a little moisture in it (was super rainy this week). I still haven't put it back in. We'll see.

Ted, Thanks for the info! Might try a new filter, just in case... Hard to tell if mine is FI and your is carbed...?

ZBane, Thanks so much for the reply! Was in the fuel hatch earlier this year... I also cleaned the AFM when I replaced the throttle body. Double-checked all vacuum and connections. Starting to wonder if it might be TPS...?

Hey, all! Well, this is a new one for me. Last night as I was driving home, the engine started bogging out when I hit about 2500 RPM. I drove almost the whole way home at 2250 RPM and 50 MPH. This morning, I started the car and headed for work. The engine revved up fine. There were no issues - UNTIL the car reached operating temperature. After reaching temp., the car bogged out at ~2500 RPM all the way to work. As I came home, same thing. The car runs fine until it reaches operating temperature. Here's what I've checked. Please let me know if I'm missing something! Fuel pressure: Normal. I upgraded the FPR in February of this year. Gauge reads fine... Fuel delivery: Good. I replaced the fuel pump and filters in February, too. Fuel injection: Good. All injectors are less than a year old. Intake: Optimal with a clean K&N filter element. Spark Plugs: Only about 10,000 miles on them. I cleaned and re-gapped them a few months ago. It is the last time I ever buy SplitFires, though. NGK for life! Ignition Coil: Replaced at same time as the plugs with new, 7mm silicone wires. Catalytic Converter: Replaced with Hi-Flo (well, hollow ) unit a couple of years ago. I really doubt it's clogged. Everything sounds great behind the car (nice clean, exhaust). Temperature Sensor: Fairly new. Replaced a few years ago. This car is driven often, but not many miles. O2 Sensor: Could this be a culprit? AFM: I cleaned this not too long ago when I installed a new throttle body. I just dropped a bunch of coin on a new transmission for my daily driver (Jeep). I still have another week (at least) before I finish it, so I really need my Z because it's the only running car I have right now. Because of my transmission woes with the other vehicle, I also don't have a lot of money to throw parts at the Z. Just to clarify, this is a normally aspirated engine. Any suggestions? PLEASE HELP! Thanks in advance for your replies! James 1980 280ZX