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Discussion Starter #1
Hey All,
So, I've been fighting the gremlin in my 2.4 with hiccuping on acceleration and 22 MPG highway. I have the car in my garage now to do a timing chain, so I'm trying to diagnose these issues, but would like to know the things to check for. I've changed o2 sensors due to a P1174 code. That went away. Throttle body got cleaned, tranny fluid and filter changed, new spark plugs, fresh oil change (every 5,000 miles). No CEL's. Anything else I can check for? Is there a way to test the throttle body module or other sensors with a multimeter? I'm at a loss. I'm trying to troubleshoot possibilities before biting the bullet and taking it in.
Thanks,
Jason
 

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Try cleaning the MAF sensor. How is it idling?
 

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Forgot to mention I did clean the MAF. It idles good at around 700 RPM. Would doing a throttle relearn help? I got the timing cover off today to do a timing chain and tensioner swap and the marks on the old chain line up with the marks on the cam and crankshaft sprockets. I also did a compression test last weekend and the results were between 161 and 165 all four cylinders.
 

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I removed the upstream o2 sensor and installed a pressure gauge to it and I saw no pressure reading. I changed the o2 sensors and pulled the battery. The code hasn't returned for at least 2 months now. Once I get the motor back together after changing the timing chain, tensioner chain and water pump, I might test the MAF sensor again with the volt meter. If nothing else, I might just bite the bullet and take it in to have it checked.
Is there any vacuum lines in the dash that I should be looking for? The lines in the engine compartment look solid. I want to check the evap solenoid too. If that was bad, would that cause these issues?
 
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