possible problem with seafoam??

[J-BABS]

I used seafoam a little over a month ago on my 89 gmc R3500, 350. The truck ran fine before seafoam, but now it stalls out when the engine is hot. I will be driving at fwy speed and all of a sudden will feel like the truck is struggling , then sometimes the problem will just go away, but when I pull up to a stop light, the truck will stall, it starts right up but it will struggle to get going . Check engine light is not on. The problem has been getting worse the past 2 weeks. I just replace the fuel filter last weekend; the fuel pump was replaced 4 months ago along with distributer. Has anyone had any problems with seafoam? That was my first time using it. Could it be spark plugs? They were replaced a little over a year ago, but less than 10k miles. Sometimes when I start the truck up when it’s cold I will hear a winding sound for a few seconds, almost sounds like ps pump, but it has fluid in it. Any ideas?

[Bowed]

I would suggest checking the fuel pressure .

[sntrym95]

When you say you used Seafoam, how did you use it?

If you got the spray can, and sprayed directly into the TBI, letting it sit to break up the carbon, you should change your plugs.

If you dumped a can into the fuel tank, it may have broken up gunk in the tank and now the gunk is clogging the screen. A fuel pressure check should tell you if that's the case, but only when the problem exists. This might be tougher to figure out. You may need to yank the bed or drop the tank and take a peek inside.

Mike

[SiCk_DiAbLo]

Never tried the stuff, but I did hear some good things and bad, did it smoke like hell when ya started it??

[BigBlocksRule]

Check the intake coolant temp sensor. When they go out, they do exactly what you're describing, the computer pours fuel into the engine to warm it up 'cause it thinks it's below freezing.

[GMC Guy]

change the plugs, and coolant temp sensor. both cheap and seafoam is known to foul plugs

[chaptr2]

Originally Posted by BigBlocksRule

Check the intake coolant temp sensor. When they go out, they do exactly what you're describing, the computer pours fuel into the engine to warm it up 'cause it thinks it's below freezing.

This is what caused me a problem. Easier fix than dropping the tank. I have also use Seafoam in my oil rather than fuel, but either way I have never had a problem because of it.