Mercury stalling issues

[madd0x]

Last month I picked up a used fishing boat with a Mercury 90hp 4 stroke. It ran fine during the test ride but once I got it out on the lake for a few long runs problems started showing up. It would randomly stall when dropping into neutral had rough starts at random, and every now and then at wide open throttle it felt like the engine was skipping a beat real hard jolts that didnt feel right. At first I blamed bad fuel or spark plugs but nothing changed after replacing them. Buddy of mine suggested checking the throttle position sensor TPS and sure enough mine looked original and pretty worn. Swapped it out in five minutes with a Torx bit and its been running like new ever since. No stalls no misfires and just clean startups.If youre chasing weird throttle issues on a Mercury 90 4 stroke dont sleep on the TPS, it was the hidden culprit for me

 

[PontoonaMatata]

I appreciate the insight! My 150 HP's setup is a bit different, but this gives me a good starting point

 

[madd0x]

I appreciate the insight! My 150 HP's setup is a bit different, but this gives me a good starting point

Glad to hear that, mind sharing your set up?