89 Caprice 9C1 O-sensor replacement

I need some FSM info on replacement of O-sensor on Caprice B-body. I've got the full police package with the 350 5.7L V8 engine.

While I'm at it, I kicked up some construction debri that punched a pinhole in the very bottom of the full tank. Was just cleaned out a year ago, no signs of rust IN the tank. Thinking I can patch this and then seal the inside of the tank....either that or replace tank (ouch).

Now have 4 5gallon gas cans of syphoned unleaded......

I need some FSM info on replacement of O-sensor on Caprice B-body. I've got the full police package with the 350 5.7L V8 engine.

While I'm at it, I kicked up some construction debri that punched a pinhole in the very bottom of the full tank. Was just cleaned out a year ago, no signs of rust IN the tank. Thinking I can patch this and then seal the inside of the tank....either that or replace tank (ouch).

Now have 4 5gallon gas cans of syphoned unleaded......

metal tanks can be patched. products are available for this. follow the directions carefully..remember an empty fuel tank can explode so no sparks.

with the exhaust hot lossen the O2 sensor. when exhaust cools completely remove the sensor. never mess with the wiring or connector. use the connector that will properly fit your vehicle. do not use a universal type sensor since messing with the wiring , can cause the incorrect voltage to be sent to the computer/pcm module.

So, patched the tank. Went the screw, washer and sealall route til I can get around to buying a new tank and dropping it. Holding quite well. Nice that the car sits so high, I can at least do that myself.

Mechanic called scratching his head. Says it can't be O sensor, cause he says it "ain't got one", and the cat seems to running fine. In fact, no lights for a few days. He thinks it's a misfire, wants to throw a ton of parts at it (sparks, wires, etc.) and do a full tune up. But, he keeps scratching his head cause he can't get into the OBD1 on board.

My car was decommissioned National Parks Service 9C1 - 89 Box Chevy. For some reason ALL identification was removed, and a new VIN assigned by MD at Glen Burnie in 2002. Even the SEO sticker is MIA. We can't even find the Fisher Tag where it should be.

And I don't like throwing parts at it cause he "thinks" he knows what the problem is.

Without the original VIN, is there a way to hack into a OBD1 to retrieve codes? My previous projects were old school (pre-computer and injectors).

So, patched the tank. Went the screw, washer and sealall route til I can get around to buying a new tank and dropping it. Holding quite well. Nice that the car sits so high, I can at least do that myself.

Mechanic called scratching his head. Says it can't be O sensor, cause he says it "ain't got one", and the cat seems to running fine. In fact, no lights for a few days. He thinks it's a misfire, wants to throw a ton of parts at it (sparks, wires, etc.) and do a full tune up. But, he keeps scratching his head cause he can't get into the OBD1 on board.

My car was decommissioned National Parks Service 9C1 - 89 Box Chevy. For some reason ALL identification was removed, and a new VIN assigned by MD at Glen Burnie in 2002. Even the SEO sticker is MIA. We can't even find the Fisher Tag where it should be.

And I don't like throwing parts at it cause he "thinks" he knows what the problem is.

Without the original VIN, is there a way to hack into a OBD1 to retrieve codes? My previous projects were old school (pre-computer and injectors).

if you have a cat converter you have a O2 sensor.



no vin # can mean many bad things don't want to go there.

this is one of those hack cars made from many different years. lots of luck trying to figure this out with out the hacker !

So, patched the tank. Went the screw, washer and sealall route til I can get around to buying a new tank and dropping it. Holding quite well. Nice that the car sits so high, I can at least do that myself.

Mechanic called scratching his head. Says it can't be O sensor, cause he says it "ain't got one", and the cat seems to running fine. In fact, no lights for a few days. He thinks it's a misfire, wants to throw a ton of parts at it (sparks, wires, etc.) and do a full tune up. But, he keeps scratching his head cause he can't get into the OBD1 on board.

My car was decommissioned National Parks Service 9C1 - 89 Box Chevy. For some reason ALL identification was removed, and a new VIN assigned by MD at Glen Burnie in 2002. Even the SEO sticker is MIA. We can't even find the Fisher Tag where it should be.

And I don't like throwing parts at it cause he "thinks" he knows what the problem is.

Without the original VIN, is there a way to hack into a OBD1 to retrieve codes? My previous projects were old school (pre-computer and injectors).

If the speedo goes to 120 MPH , with 2mph increments , it is the police pkg.

Should be able to flash codes, by jumping "A" to "B" in the ALDL connector....then turn key to run, don't start....should flash "12" 3X's, then flash the first code 3X's, and any more codes 3X's.....when it flashes "12" again, it's the end of the codes....

If your mechanic says your car doesn't have an O2 sensor, I'd be very leery of him....

Should be able to flash codes, by jumping "A" to "B" in the ALDL connector....then turn key to run, don't start....should flash "12" 3X's, then flash the first code 3X's, and any more codes 3X's.....when it flashes "12" again, it's the end of the codes....

If your mechanic says your car doesn't have an O2 sensor, I'd be very leery of him....

To clarify the above - CODE 12 breaks down as follows -

One short flash, pause, two short flashes - longer pause - (repeat 2 more times).

Code 45 would be flash flash flash flash short pause flash flash flash flash flash long pause repeat 2 more times.

If you have access to a laptop and can fashion a cable, you can download software called WinALDL which will give you real time scanning capability when hooked to the ALDL port (with the engine running).

ALDL = Assembly Line Diagnostic Link. It's underneath, and to the left of, the steering column. It has two rows of 6 pins.

Also, for a 1989 Caprice 9C1, the speedometer will read to 120MPH in most cases, all others will be 85MPH.

Also, what flashes - will be your MIL (Service Engine Soon).

Last message was helpful, I did something similar to read off semi's in '92 for a trucking company - not diagnostics so much as snooping on driver's bad habits. Imagine a truck battery, modified jumper cables and a dot matrix printer....yeah, still not sure why the office didn't blow up....

...Yeah, fired that mechanic. Grrrr. Just should do this myself. Figured it be faster since he has a lift and tools and space to work and is supposed to be state certified to do the inspection sticker as well....around here inspection stickers come from mechanics...you can guess the trouble I have driving up (I'm a girl) with the Zombie (aka rust bucket).

...as for the suggestion my car is a frankenstein or stolen...Found out that when the Nat Parks decommissioned it, they sent if off to salvage (they did cobble together some bits in the spirit of "maintaining" the fleet - but while it may have some transmission bits from another 89 Parks car...it's all OEM). Hence, the VIN was reported scrapped. Dealership bought it, and had a new number assigned. Car was never stolen, it's what Glen Burnie, MD does when a title is "lost, or reported salvaged". By the way, in MD, if you replace an engine, transmission or a "significant" portion of the chassis, they rip out the VIN plate and give it a new ID as well.

Definite 350 (total 9C1 package), lookin at it right now. The ONLY way to get a box chevy with the 5.7L was a police, fire or in my case a park's car. Though I think from other Pc1 forums, some taxicabs had the same package? Straight from from Arlington, TX in all TAN& puke beige. She's still got her original paint complete with green stripe under a spray of hunter green from a can.

Last message was helpful, I did something similar to read off semi's in '92 for a trucking company - not diagnostics so much as snooping on driver's bad habits. Imagine a truck battery, modified jumper cables and a dot matrix printer....yeah, still not sure why the office didn't blow up....

...Yeah, fired that mechanic. Grrrr. Just should do this myself. Figured it be faster since he has a lift and tools and space to work and is supposed to be state certified to do the inspection sticker as well....around here inspection stickers come from mechanics...you can guess the trouble I have driving up (I'm a girl) with the Zombie (aka rust bucket).

...as for the suggestion my car is a frankenstein or stolen...Found out that when the Nat Parks decommissioned it, they sent if off to salvage (they did cobble together some bits in the spirit of "maintaining" the fleet - but while it may have some transmission bits from another 89 Parks car...it's all OEM). Hence, the VIN was reported scrapped. Dealership bought it, and had a new number assigned. Car was never stolen, it's what Glen Burnie, MD does when a title is "lost, or reported salvaged". By the way, in MD, if you replace an engine, transmission or a "significant" portion of the chassis, they rip out the VIN plate and give it a new ID as well.

Definite 350 (total 9C1 package), lookin at it right now. The ONLY way to get a box chevy with the 5.7L was a police, fire or in my case a park's car. Though I think from other Pc1 forums, some taxicabs had the same package? Straight from from Arlington, TX in all TAN& puke beige. She's still got her original paint complete with green stripe under a spray of hunter green from a can.

If the vehicle was sold as scrap/salvage etc. the vin# removed. the state would have to do a complete inspection to get this approved to be registered .

since this 1989 vehicle has no O2 sensor I doubt this was done. If this was in original condition all the parts/engine etc . the price for this police caprice , is quite high when compared to any other 1989 caprice.