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2003 Nissan Altima

115,000 miles. Runs terrible! Barely idles. Multiple misfires. Changed plugs, examined plug cores, checked PVC and changed air filter. No improvement. Finally poured a full can of Sea Foam 16 oz into gas tank. Ran it down interstate and drove for about 15 miles, at about 70-80 MPH, running bad, but then began to run smother. Got off interstate filled up tank with Shell (or other BRAND NAME fuel) and it has run better than ever! Searching internet help me find this possible solution. Full can was advised to be ok, ratio no greater than 4 oz per gallon of gas.

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what causes 2005 2.5l volvo to misfire and show code random multiple misfires i replaced plugs but no good

I would take it back and demand a refund. Could be the crank or cam sensors, an intake leak, faulty coil, or a list of other components.

Aug 26, 2012 | Volvo S60 Cars & Trucks

1 Answer

my 1998 dodge stratus is running normal when going down the road but soon as i stop it has a rough idle and is under the one on the rpm and recently we changed the pvc valve and it wont run with it hooked up but when we leqve it unhooked it wont stalll at the a stop anymore but still has a rough idle to it

First you need to hook up that PVC valve hose because you are sucking countless containments into the engine. Sounds to me like your MAF sensor might be malfunctioning. I would clean it and perhaps replace it. When is the last time you changed your air filter? If it is to clogged this can starve your vehicle for air. You spark plugs could also very well be fouled. Your car is more than likely misfiring all the time but it is much more noticeable at a stoplight. I would recommend you first clean the MAF sensor. Check the air filter. Clean the throttle body and if non of that help do a tune up. Regards, Tony

Apr 14, 2011 | 1998 Dodge Stratus

1 Answer

multiple cylinder misfire detected

Thank you for all the information. I don't see how you made it worse unless the injectors were not installed correctly. If you remove them you are suppose to replace the o-ring on each of them and oil them (the o-rings) before installing them. I would check the air filter and the CAT (for excessive back pressure. Also check the rest of the exhaust for damage. If a pipe is kinked or flattened it would need repair. Also GM's are known for some issues with there e-vap systems. You may want to check it out. The gas cap, charcoal canister, vacuum lines. Well good luck.

Apr 16, 2009 | 1997 Chevrolet Lumina

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