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EDZIP
04-04-2017, 04:33 AM
Received a call from a neighbor who building a father/son race car for our local dirt track. This is the first year of the Strictly Street class (4cyl). They have a 2003 Chevy Cavalier 2.2 5sp. They began stripping the car down to reduce weight, built a cage and want to run a basic OBD2 managed engine. Haven't seen the car yet but he says after removing some parts it will now start, run for about 5 seconds and shuts down. Going to run over there tomorrow with my scanner to help them get this project going - BUT FOR THE FUTURE:

Looking for suggestions to help set him up and probably someone to flash his PCM (or two). Since it's strictly for the track should it be set up for open loop etc? Won't have downstream O2 etc. Attached a pin-out from my MOTOR MANUAL and it has a bunch to be disabled and I hope to clean up the wiring.

Thanks

1project2many
04-04-2017, 02:59 PM
I love four cylinder racing classes. There were several guys on j-body.org that were into the 2.2 engines several years ago and we came up with some good tricks. One of the forum members and a partner ran two cars and had some success at a small track in the midwest until the track killed the class. Then they raced with eight cylinder cars until the other guys put up a stink. I believe the team purchased hptuners to make changes to the stock ecm. Custom cam, solid lifters, custom intake, larger injectors, ported head. PE mode almost always, and maybe a trip to the dyno to help dial it in. Disable any cat temp protection, any security system goodies. 5 seconds to stall sounds like security system protecting car.

https://www.youtube.com/watch?v=uYi_BXnyFwQ
The good stuff begins about 2 1/2 minutes in.

https://www.youtube.com/watch?v=wXWebvVXnIU
Another of the same car on a wet track.

dave w
04-04-2017, 03:11 PM
It appears HP Tuners supports the 2003 Cavalier 2.2 liter.

dave w

EDZIP
04-04-2017, 03:25 PM
What is the cost to get set up with HP Tuners for OBD2? Also, will there be relearn procedures after flashing?

1project2many
04-04-2017, 04:23 PM
Without O2 feedback there isn't much to learn other than IAC position.

HPTuners:
https://www.hptuners.com/order.php

EDZIP
04-04-2017, 09:34 PM
Thanks

Can this vehicle operate operate without the BCM (PCM only)?

EDZIP
04-05-2017, 03:39 AM
What obstacles would there be to convert the car to OBD1?

1project2many
04-05-2017, 04:16 AM
I honestly can't remember ifyou can run the OBDII controls without the BCM. I spent some time on J-body.org looking at old posts but I couldn't find an answer. I believe the BCM is married to the PCM and the only way to divorce them is with tuning software. You can force the starter to crank but the ecm will kill fuel if the BCM signal isn't present.

OBDI swap can be easy if you don't care about keeping any of the factory gauges. A 95 ecm will work in the fenderwell and be OBDI but will probably need wiring changes. Older ecm's will work but they should be moved into the car and would need complete tuning.

EDZIP
04-05-2017, 05:01 AM
I honestly can't remember ifyou can run the OBDII controls without the BCM. I spent some time on J-body.org looking at old posts but I couldn't find an answer. I believe the BCM is married to the PCM and the only way to divorce them is with tuning software. You can force the starter to crank but the ecm will kill fuel if the BCM signal isn't present.

OBDI swap can be easy if you don't care about keeping any of the factory gauges. A 95 ecm will work in the fenderwell and be OBDI but will probably need wiring changes. Older ecm's will work but they should be moved into the car and would need complete tuning.

This is a race truck so factory gauges won't be used and ECM placement is not a problem. I have extra 747 ECMs with eprom socket conversion and 730 ECM's and have made TPI and LT1 wiring harnesses. Just drawing a blank as to were to start specifically with "ignition management". Then I could use my OBD1 software.

dave w
04-05-2017, 06:24 AM
It appears the 2003 Cavalier has a Crank Position Sensor with a Coil per Spark Plug ignition system. I think keeping the Cavalier OBD2 is a good plan. Hopefully there is someone in your area with HP Tuners who would be willing to custom flash the Cavalier computer to a "Stand-Alone" or "Race" flash. If your successful finding help with a Stand-Alone flash that gets the project moving in a positive direction, then it might be a good plan to purchase HP Tuners for yourself?

There is a machine shop near me that has HP Tuners, so if you are interested, send me a PM for their contact info.

dave w

1project2many
04-05-2017, 11:42 AM
The four cylinder ecm's are not well supported. GM was kind enough to sell two different 2.2 engines in Cavaliers from 2002 to the end of the model. You attached wiring diagrams for a 2001 - 2003 engine which should be the OHV engine rather than the Ecotec but at would be good to get clarification. Ecotec changes everything.

EDZIP
04-05-2017, 05:16 PM
Thanks guys...the more I look into this the more of a mess it becomes for being a 4 cylinder engine. The guy cut most of the wires (want's toggle switches), the car now starts and runs for a few seconds, obviously VATS related. He has the Passkey setup (chip in lock not the key), so I'll run over there with some resistors and wire one in. Found a bunch of online videos with Passkey relearning. Another problem is that he doesn't have the instrument cluster so I can't work with the "security light". One site http://www.bergerweb.net/PasslockFix/ indicates that any resister 470 to 11800 ohms can be installed and learned.

Would like to bypass the BCM altogether but doesn't look good...still looking for a BCM wiring diagram.

1project2many
04-05-2017, 09:57 PM
I believe I have wiring diagrams, or at least pinouts, in a spreadsheet at home. I'll look tonight if it's not too late.

EDZIP
04-05-2017, 11:11 PM
I believe I have wiring diagrams, or at least pinouts, in a spreadsheet at home. I'll look tonight if it's not too late.

That would be great..no hurry can't look at the car until Friday anyway.

Thanks

BTW: He is willing to pay for any flashing.