This all started in February 2009 when I went to turn the car on after being in Walmart and it bogged down and wouldn't restart. A half hour later, it started and ran. ran injector cleaner through it. Ran fine for a week, then did it on the next full tank of gas. 30 minute later it would start with no prob. Two months later it throws a SES- P0171. Get it cleared. It comes back. Now the rough starts are frequent. I cleaned the MAF and replaced the MAP. SES went away for a week then came back while I was sitting in traffic on the highway. Once it finally starts and warms up, I can restart it at will with no problem, until it cools down. Always starts rough now.
Fuel pump wouldn't not work at start then run fine and car starts when warm. Could be 02. Have run injector cleaner through it. It's not the MAP or MAF. No vaccum hoses leaking. Already replaced Fuel filter. What is causing this?