1wiperDude

I have a 97 civic EX stock d16y8, replaced the bottom end with a motor with 50k on it about 2 years ago, using an automatic harness from an EX, stock ECU

Recently replaced: OEM Head gasket, timing belt, water pump, OEM thermostat, ARP head studs, new valve cover seal with spark plug seals, new spark plugs, cap/rotor, coil, Mishimoto Rad with slim fan, and OEM hoses. Other mods include Cold air intake, 2.25 exhaust, 8.3lb flywheel and ACT "heavy duty" clutch.

Timing is perfect, starts right up every time. Adjusted the idle so its around 1k rmp.

However, throwing 2 CEL's #22 for VTEC oil pressure switch (tried 2 different y8 switches and still get this code), and #91 for FTPS. If you have any input on how to rid of them that would be helpful but my main issue is listed below.

When I drive the car, and for example am in 2nd gear and I press the clutch pedal to the floor, the car will stall. Sometimes when at operating temp and its idling, the car stalls as well when the clutch is pushed in. Read some threads about injectors might be clogged or bad fuel pump, but I don't get how that would be my issue if it start fine. Another thought I had was maybe due to the lightened flywheel it causes the RPM level to drop due to lessened weight on the motor. Any input on what is causing my stalling would be great. Sorry this is so lengthy but I figured the more people know the better they can help.

Former User

I would fix code 91 (EVAP fuel pressure sensor) and go from there.

There are three different code 91s. Pull the code with an OBDII scan tool to focus troubleshooting of this code.

thelate1

Hmmm, from what we found, a 91 code was fuel tank pressure. If it's an EVAP thing, then we can check that out....

Former User

This sensor is part of the EVAP system.

thelate1

Sweet, thanks. So that sensor is in the gas tank, or by the canister in the bay?

Former User

In the gas tank.

thelate1

Ok, so we are looking at #1 I'm guessing?

http://www.hondaautomotiveparts.com/...L+TANK+%282%29

1wiperDude

I dont get how a sensor is $135. it Prob costs $20 to make it tops.

thelate1

Up for any other things we might be overlooking.....

1wiperDude

yeah cause we all know when you think too hard about crap for hours on end you overlook the complete obvious and stupid simple stuff....

Former User

Take the car to AutoZone so that they can pull the OBDII code for you. Post this code, and then I will post the troubleshooting diagrams. You don't want to purchase a new pressure sensor assembly without knowing whether it is bad.

thelate1

Thanks, that will be a huge help. Hopefully we'll get there this weekend.

1wiperDude

Ok went to Autozone, worse then I thought. 6 Codes came up but 2 were "stored" codes.

Codes were:

P0113 - IAT sensor circuit high voltage (this sensor is nonsense IMO)
P0325 - Knock Sensor circuit malfunction (my knock sensor is broke I know this)
P0453 - FTP sensor circuit high voltage
P1259 - VTEC system malfunction (open circuit, solenoid or pressure switch fault)

The 2 stored codes were:

P0450 - I think this is/was for my IAC sensor, can someone verify this?
P0505 - this is said to be, "Evaporative Emission Control System Pressure Sensor Malfunction" can someone verify this?

Don't know why they are "stored" and what that really means. Can anyone clarify so I can better understand?

Any help would be great. I decided to get another 96-98 5 speed harness comes with the ECU as well..to try to fix some of these issues. Any other suggestions?

Former User

The first step is to reset the ECU by removing the 7.5A Back Up fuse under the hood for a few minutes. Then drive the car around the block and pull the codes again. You only want to troubleshoot CEL codes that repeat.

Former User

I think that P0450 is probably just a generic code to indicate a malfunction in the fuel pressure sensor circuit.

P0505 indicates an IACV mechanical problem or a vacuum/intake air leak.

1wiperDude

Thanks for the help, I'll do this and get my buddies OBD-II scanner and check to see what I get.