Well I got my car back together with all the new rear end stuff and I have started driving it again (down for 8 weeks.) The car is a 95 T/A. Symptoms: As I drive and slowly start to accelerate, about 3500 rmps the car starts to miss and at 4500-5000 the car hits a wall(this also does this in nuetral when slowly pressing the petal) and rpms drop to 3500. The car also is putting out black clouds of smoke when this occurs. Tests so far: Fuel pressure is fine, no "ses" codes, and when I punch it in nuetral, It hits 7k rpms no problems just like normal. Ive tested the tps, maf, map and they are fine. Left and right BLMs are 100 and INT is 79-81. The car is acting like there is a revlimiter at 4500ish RPMs. On a side note, isnt the fuel pressure supposed to stay energized? After my pump shuts off after the initial key on, the fuel pressure drops back to zero and after I shut the key off after the engine has been running. No problems starting though. Any help or suggestions appreciated. Thanks in advance.

 

When you turn the key on, the pump should run for 2 seconds, then shut off the pump. Pressure should be in the 40psi range, and should hold there for a while, dropping very slowly, if at all. If it drops immediately, you have a leaky injector, a faulty check valve in the fuel pump, or a faulty fuel pressure regulator.

You say the fuel pressure checks OK. What psi did you get at idle, with the vacuum line disconnected? How much did the pressure drop when you reconnected the vacuum line? Was there any sign of raw fuel in the vacuum line? What is the fuel pressure at WOT when the engine starts breaking up?

The PCM is pulling fuel like crazy (BLM's can't go lower than 108, so recheck your data), and you say there's black cloud coming out of the exhaust. Misfires will cause that, so you have to look at the ignition system and the fuel system. Excessive fuel pressure would be one possible cause, a ruptured diaphragm on the FPR, and leaking injectors. The leaking injectors would explain why the fuel pressure drops when the key turns off, and it also explains the low BLM's. As the excess fuel pour out the exhaust from the leaking cylinder, it consumes the O2 that's left from the other cylinders and you get a false rich reading on the O2's.

Pull the fuel rails, with the injectors intact. Turn the key to on and let the fuel system pressurize (do not try and start engine, better doen when engine is cold to reduce fure risk). If there are leaks in the injectors you will see them.

After you rule out the fuel problem with a correct fuel pressure check and a visual for leaky injectors, you'll have to start looking at the ignition.

 

Thanks for the input. Actually the blms were 100 but I found the problem tonight trying to solve the fuel problem. When taking everything apart I found that I blew one of the supercharger pipes apart and that it was throwing all the air measurements off. The fuel problem is in the regualator. Kinda pisses me off since it is a fairly new Aeromotive APR and I took it apart and cant find anything wrong with it. I can suck through it fairly easy though. Any suggestions? I took a large drill bit in my hand a spun it pretty carfully on the seat. It helped but still leaks down within 10 seconds.

 

Aeromotive offer a free replacement, no questions asked on some of their AFPR's. Do a search, there's an Aeromotive rep who posts on here and can give you a return authorization.

Looked at literally HUNDREDS of data logs, and never saw a BLM go below 108.

 

I have a snap-on scanner if that makes a difference. Also a BLM cell of 2 when they were at 100. Now that it is running right again, is it normal for the left to be different from the right L=119 and R=141? I never really paid that much attention to them before.

 

Not good.... that's called "split BLM's". What are the BLM's for some of the other cells, including 16 for idle, and 15 (max rpm/MAP)?

You want them close to 128 and you want them close to each other. Right now, at low load/low rpm your PCM is cutting fuel 7% on one side and adding fuel at 10% on the other side. Split BLM's may occur only at idle and low loads with certain throttle bodies and cams. If they are split all the way up to max load, you have a problem on at least one side that needs to be identified and corrected.

 

Yes, the old Split BLM problem. I have done quite a bit of research and here is my conclusion. If you have a big cam and a aftermarket TB you probably have split BLMs, this should clear up once the car is above 2500-3000 RPMs. If you have Split BLMs across all load conditions and RPMs as Injuneer stated you have a problem. THe most comon reasons for Split BLMs are vacuum leaks, exhaust leaks, bad plug wires or fouled plugs. I did a search on split BLMs and found a lot of good info. As for the AFPR you need to pull the vacuum line and see if there is any fuel in it. If there is quit running the car disconnect the AFPR and replace it. If the diaphram is broke it will fill the cyl. with fuel and hydro lock the motor it just happened to a freind of mine.