Fuel filter change, now service engine soon light

Hey guys,

I recently replaced a clogged fuel filter and now the SES light comes on after starting my '87 Caprice estate 307. Let me walk you through what I did:

1. The car had been rough starting and finally wouldn't start at all after repeated attempts.

2. Took off the air cleaner and snorkel hose and looked into the carb while opening the throttle and noticed that gas was not reaching it.

3. Disconnected the distributor bat cable and then disconnected the fuel line and saw that gas was coming out when the starter motor was operated.

4. Removed and replaced the clogged fuel filter.

5. Replaced air cleaner and all hoses.

The car seems to run fine now, except for the fact that the SES light trips after startup. Anyone have any idea why this could happen?


Thanks,

Alex

Hey guys,

I recently replaced a clogged fuel filter and now the SES light comes on after starting my '87 Caprice estate 307. Let me walk you through what I did:

1. The car had been rough starting and finally wouldn't start at all after repeated attempts.

2. Took off the air cleaner and snorkel hose and looked into the carb while opening the throttle and noticed that gas was not reaching it.

3. Disconnected the distributor bat cable and then disconnected the fuel line and saw that gas was coming out when the starter motor was operated.

4. Removed and replaced the clogged fuel filter.

5. Replaced air cleaner and all hoses.

The car seems to run fine now, except for the fact that the SES light trips after startup. Anyone have any idea why this could happen?


Thanks,

Alex

with this engine I'm guessing its the O2 sensor. I would get the failure code and post this here for what is wrong.

the reason I say it may be the O2 is , this would cause the engine to run very good with the O2 not correct in operation .

I would replace the fuel filter after a few thousand miles . these metal fuel tanks with alcohol are a big problem with rust generation. If you have the old filter use a magnet to see if it is rust .

add a few ounces of marvel mystery oil to each fill up, or 1-2 ounces per 10gallons of fuel. this will clean up and protect from future tank corrosion.

the SES light trips after startup. Anyone have any idea why this could happen?

Have the car checked for codes and post back your findings. It's really hard to guess what it might be..

I agree with Blt2Lst above, check the codes. You mentioned that you disconnected some wiring from the distributor. Check the 4-wire connector to the distributor to make sure it's making good contact. If it's disconnected, this is your light.

Alright guys,

Checked the codes and here's what I have:

21: Throttle position sensor high during idle or decel.

44: Lean exhaust indication

Alright guys,

Checked the codes and here's what I have:

21: Throttle position sensor high during idle or decel.

44: Lean exhaust indication

Sounds to me like you may have carb issues. I had the same codes before i had my carb rebuilt last December, turns out the TPS was bad and a worn throttle shaft caused a vacuum leak causing my lean condition. The worn shaft is common to the q-jets. The carb rebuilt took care of those problems along with my unsteady idle.
If you are going to take the carb apart to replace the TPS, you might as well do a complete rebuild. :2cents:

Also, check all the vacuum lines (and there are a lot of them), chances are they need replacing also.

The carb rebuilt took care of those problems along with my unsteady idle.
If you are going to take the carb apart to replace the TPS, you might as well do a complete rebuild. :2cents:

Also, check all the vacuum lines (and there are a lot of them), chances are they need replacing also.

Thanks Blt2Lst, can you or anyone else point me to a good reference on rebuilding the carb? I have the Haynes manual but not sure if that is enough by itself.

Also, how long can the car be driven in this condition/is any harm being done to it driving like this?

Much thanks,

Alex

unplug your o/2 and see if any change. have you tryed resetting your computer? if not take neg cable of for about 15 min. or so and it will reset your computer when you hook cable back up.

HELLO. In your initial post you stated that your engine was a 307 (OLDS ENGINE maybe?). Is this what you have? Or do you have the CHEVROLET 305? Is the carb a 2bbl or a 4bbl? This info might or might not make a diffrence in the expertise within the replies you receive. When the O2 sensor went bad on my 84 CAPRICE it did not throw a code via the SES light. It just ran like it was starving for gas, good idle but on a hard/steady pull it would just lie down, cut out etc.

HOPE THIS HELPS

The Olds 307 came with the Q-Jet carb.
A rebuild kit usually comes with directions and a exploded assembly diagram.
The TPS is a separate part not included in the kit. Also, if the throttle shaft has excessive play, you would need to get a bushing kit which would also include a reamer of the correct size.
Or you could have someone else do the rebuild.

These are the guys that rebuilt mine.

http://www.smicarburetor.com/products/sfID1/85/sfID2/86/sfID3/34/productID/432

SHAWN MURPHY INCORPORATED. Good stuff. Check em out on the web.

SHAWN MURPHY INCORPORATED. Good stuff. Check em out on the web.
+1. And great prices.