[washm]

I just change my brake light switch (36750 SMA 003) and the spark plugs. I install NGK PZFR6F-11(I know I should have went with NGK PZFR5F but I ordered the wrong ones. My question is when I drive about 10 miles the van starts to decrease in speed. It all most seems like it the brakes are being press to all most brings the van to a complete stop. I get out and pull brake light switch (36750 SMA 003) out and bam the van drives normal for about 10more miles. What do you think may cause the problem???

Any advise will be greatly appreciated ....

 

[William Wiles]

Try putting the origonal plugs back in.

 

[washm]

Went to Advance Auto and purchased the original spark plugs lastand the same thing happens.. Strange, I will do alittle more intense troubleshooting once Hurricane Irene pass.

Thanks for your feedback...