2000 Chevy Blazer cutting out

I have a 2000 Chevy Blazer with about 180,000 miles on it. It has been running fine, then a few weeks ago we got gas at a small little station we had never been to. The day after it started cutting out. We took it to the shop and they put a new catalytic converter on it. They said it also needed a new water pump and something with oil seals, so we went ahead and did that. It drove fine for a while, then the next time we filled up with gas it started cutting out and completely died. They put a new fuel filter, spark plugs and wires and distributor cap, basically gave it a good tune up. It’s been driving fine. We filled it up and with in a few miles it start stuttering. At the stop light it rattled but kept going. drove it another 3 miles and it stuttered again. We are out of money and at our wits end! Any ideas?

Take it to an auto parts chain and have them read the trouble codes with an OBD scanner. Write down the exact codes if any, e.g. P0443. Be sure to write down the exact letter/number comination and not just the general description that the auto parts guy gives you. If there are any codes, they may give more insight into the problem. If not, welll the attempt was free.

Why would your shop replace the catalytic converter to solve a stalling problem?

Some possible causes: bad ignition switch due to wear, or too many keys on your keyring. Cracked ignition coil. Bad crank angle sensor. Water in the gas from your “little station.”

Try dumping a can of gas treatment (the kind that absorbs water) into your tank. It may or may not help, but it’s a cheap fix if it helps. Don’t go back to your “little station,” if in fact there was water in their gas.

But it could be entriely unrelated to gas, if it’s electrical like a bad ignition switch, coil, or crank sensor. If the problem persists you’ll have to find someone who can diagnose it and not just throw parts at it.

Sounds like fuel is entering the vacuum return line when you fill up. Check the vacuum hoses that come from the gas tank to the engine and make sure you are not sucking in fuel. Try running for a while with only a half tank of fuel and see how that works. You may also want to check/replace the gas tank filler cap. This cap must seal properly so the tank maintains the proper pressure, some systems are a bit finicky about this item.

If above aren’t the problem, you might need to have the gas tank completely drained, then filled with known good gas. You may have just got unlucky and got some contamination in the tank. When you put in new gas, it stirs it up and allows it to flow to the engine.

Without knowing the OBD codes, sounds like a worn fuel pump. Other than the fuel filter, the shop you paid to repair this issue is clueless and looking to take advantage of your ignorance.