now the car bucks and surges but it starts fine now
Ford Q&AAsk Your Question
1990 Ford Thunderbird SC Question: the car was hardstarting so i replaced the camshaft positioning sensor...
Answer #1patrick mannion from Greg Solow's Engine Room, December 02, 2011, 22:08Master
Start with the basics, spark plugs good, no vacuum leaks,perhaps check compression is even in all cylinders, look at the old spark plugs see that they are all the same color, none are mechanically damaged or oil fouled.
PARTS GUY December 03, 2011, 14:08Master
Your check engine light must be on. What are the trouble codes?
Replybama07football, December 04, 2011, 00:24Enthusiast
there is no trouble codes check engine light is not on...it ran great before i changed the cps but it was hardstarting...i changed all the plugs,wires and coil...no vacuum leaks were detected...all the old plugs were evenly worn no oil on them..compression was good on all 6 cylinders...i unplugged the cps and now it runs good again but is hardstarting again...and i do run premium gas in it...is it possible i bought a defunct cps