So I've got a '98 tracker motor installed in an '87 Samurai. Here's my problem:

At Idle, the engine runs great, but when I give it gas (at a moderate to fast pace) it bogs out (so bad it will just die, in gear or out of gear). If you give it gas REALLY slowly, it will rev up and you can sort of drive it. I checked the timing multiple times, and it is at +5 TDC. I also verified the timing belt was correct. The fuel pressure is 50psi prior to start, and 41-42psi at idle (aftermarket fuel pump, E-2000, commonly used in this motor swap). I also ran codes, and got an O2 sensor failure, but I'm pretty sure the O2 sensor wouldn't affect throttle responce because the O2 sensor doesn't even affect the motor until the temp is up.....
So why is it bogging out? Brand new spark plugs, too.
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Ok, Here's some more info:

The motor is a '98 Tracker 1.6 16valve.
Yes, I used the origional tracker ECU, and wiring harness.
Yes the check engine light is on, but it is primarily due to the fact that I have a Samurai gas tank, and therefore the sensor that should be in the tank is not there. Also, with a Samurai gauge cluster, I have no VSS, also causing a CEL.
Here is the codes I got:

P0135 (O2 sensor heater, circuit malfunction, bank 1 - sensor 1)
P0450 (EVAP emission control system pressure, sensor fault)
P1410 (manufacturer control, aux emission, controls)
P0135 -again
P0300 (random/multiple cylinder misfire detected)
P0450 -again

So I assumed some of these codes came from screwing with the timing so I erased the codes and ran the car for 10 min, then gave it enough gas to kill it. What resulted was two codes:

P0135 & P0450

(Bank 1, Sensor 1) is the O2 sensor in the exhaust manifold, right?

Could be a clogged fuel filter, you have to check for that by watching
the fuel pressure as you drive.

The O2 could be giving you a lean condition and causing your problem,
they don't go bad often so check the wire to see if it's connected, even
the 3 wire sensors will work without the heater wire powered, it's just
faster to warm up and run better when it is heated

Wild

The fuel filter is brand new... I replaced it when I did the motor swap, and I have not driven it more then a mile since the swap due to this issue.
I will check the wiring of the O2 sensor, and get back to ya.....

also check your fuel line size(has to be large enough) and take out the little plastic one way valve by the tank.

also check your fuel line size(has to be large enough) and take out the little plastic one way valve by the tank.

Yeah, I did all that. However, I did notice that the fuel pressure spikes to 50 psi when I nail the gas. Is that normal? Otherwise, the fuel pressure during idle and OFF is great. holds pressure for 10 hours after shut-off.

That's odd, fuel pressure should remain stable or drop slightly, but not spike, tho
50 PSI isn't really enough to cause too much trouble, unless the pintle is having
trouble lifting in the injectors from the pressure increase

Wild

That's odd, fuel pressure should remain stable or drop slightly, but not spike, tho
50 PSI isn't really enough to cause too much trouble, unless the pintle is having
trouble lifting in the injectors from the pressure increase

Wild

Huh.... So how can I check this?

Pinch off the return line, see if it stalls the engine or runs better.

I bumped the pressure to 80 before the TBI injector couldnt over come
the increase in pressure. This was when I was playing with the turbo tuning

Wild

That's probably the small diaphragm in the front of the fuel rail with the vacuum hose on it, I think that is supposed to do that.

That's probably the small diaphragm in the front of the fuel rail with the vacuum hose on it, I think that is supposed to do that.

No, that's the fuel pressure regulator.

pull the hose on it and look for fuel or smell the hose if you can, they do go bad or get sticky from the new fuel.

I had the same issue and after taking it to my mechanic... he found that the run of the miss plug wires I put in was arcing over to the valve cover and causing the motor to do exactly what you described. We installed dome expensive (extra insulated) wires and I never had that issue again.

Zig

he may have coil packs instead of wires and also the vss not being hooked up will sometimes make it run bad and have bad mpg.

OK, Ive tried to follow and I wold like to put my 2 cents in.

you said you have a front o2 sensor heater circuit and evap pressure sensor codes. if erased the codes will reset as soon as the ignition is turned on.  The logic senses an open circuit. Neither code will cause a running issue. But tracing the harness may lead you to the source of the driveability problem.

the hesitation can be caused by allot of different issues. do you get black smoke when you are trying to accelerate?

when you talk about the fuel system, plastic and filter were mentioned, If a factory style 87 samurai filter is used is it on the suction or pressure side of the pump?

IF YOU HAVE A PLASTIC FUEL FILTYER ON THE PRESSURE SIDE OF THE FUEL PUMP YOU ARE DRIVING A TIME BOMB! The plastic filter is not designed to hold pressure, especially not 40 to 80 psi.

i think you are using the original Sammy tank and have an external pump, (with the filter between the tank and pump). If the pump can suck air due to a cracked hose, bad hose connection, or rusted pickup tube in the tank, air will compress and cause the symptoms that you are experiencing. (still give the appropriate gauge readings) if there is air entering it is likely the pump will be very noisy.

no speed sensor signal will not cause hesitation upon rev up.this signal is used for egr and ignition timing control.

Who has converted the harness for you? I'm currently doing an obd2, 98 model year, and i will tell you that there is allot more to consider that there has been on all the obd1 (95 and earlier) Ive done.

use the front o2 sensor and a meter to tell you if it is rich or lean. hook a volt meter to the shielded wire and measure the voltage during the incident.  .5 volt and above is rich, .4 and below is lean. upon accell i would expect to see about .7volt.
Or if you can get a scan tool you and watch the o2 sensor and fuel trims.

lets start there and if that doesn't get it post me the results!

Ok, so I replaced my spark plug wires and my O2 sensor. It actually runs much better now....
However, it still bogs out when I stomp on the gas so bad that it dies....
How do I test to see if my timing is advancing?
And how much will the dealer charge me to check the ECU?

You all have been so helpful.... Keep the ideas coming!!!!

Also Here's some answers:

No black smoke when I accelerate, but some water out the pipe....
I am using a steel ford expedition fuel filter, between the stock Sammy tank, and the pump.
I converted the harness myself, but for the fist time.