Trembling/Pulsing Engine Options

[AustenJoe12]

Hey guys, so I have a 95 GT and just recently (like it just started today) my car started trembling but only when I am at a stop light. When the car is idling at a stop light it starts to pulse and tremble as if it's going to die off. I can not only hear the trembling but I can feel it in the pedals. The car is also running really sluggish and I already changed plugs, cap, and rotor (because they were never changed). My car was also sitting when I was trying to get my transmission figured out. I was told that I should change the fuel filter because the car has been sitting for the better part of 6 months with ethanol fuel in it. I was wondering if any of you guys had this problem and what you did to fix it. Anyone that could help I'd really appreciate it.

[RabidTRD]

Try running some seafoam through the fuel system with fresh mid grade or higher in it. It's possible the octane dropped a level and you've got some separation. Wouldn't hurt to change the fuel filter too. Also, if it's been sitting 6 months, it wouldn't hurt to change the oil.

[AustenJoe12]

Try running some seafoam through the fuel system with fresh mid grade or higher in it. It's possible the octane dropped a level and you've got some separation. Wouldn't hurt to change the fuel filter too. Also, if it's been sitting 6 months, it wouldn't hurt to change the oil.

Yeah I changed the fuel filter and the plug wires and now it's not trembling anymore. I ran sea foam when I got my car back and I'm gonna do it again and start running non-ethanol fuel. I have to do an oil change and I will probably put lucas oil additive so that it's all good.

[Galcobar]

The 10-15 per cent ethanol in standard gas won't hurt a Japanese engine from the 1990s or newer. The damage to hoses was confined to natural rubber hoses (old tech) or domestic manufacturers using less resilient materials. Our engines had no compatability issues.

However, ethanol is also good at dissolving carbon deposits. In a clean engine, that's not an issue, nor is it (generally) in an engine which has been regularly running ethanol-mixed or high detergent (Top Tier) gasoline. In an engine with a lot of miles and some buildup, ethanol carries the same danger as other deposit-removing cleaners, such as Sea Foam.

They can loosen deposits and set them free into the fuel system before it's completely dissolved to plug up a filter or fuel line -- rather like a clot breaking free and causing a stroke by blocking blood flow. The fuel filter's the most likely to clog, because that's its job; it catches all the crud built up in your tank and fuel lines before it gets into the delicate parts of the fuel system, and it's a lot cheaper to replace.