texasfishingforum.com logo
Main Menu
Advertisement
Affiliates
Advertisement
Newest Members
Junkguy, lucamask, Fishing A lot, JeffStephens, budgetfisherFW
118332 Registered Users
Top Posters(All Time)
TexDawg 114,545
hopalong 112,874
Bigbob_FTW 88,376
John175☮ 84,659
Pilothawk 82,892
Bob Davis 69,677
Mark Perry 68,941
Derek 🐝 68,072
JDavis7873 67,416
Forum Statistics
Forums59
Topics1,156,639
Posts15,813,933
Members143,332
Most Online36,273
Jan 23rd, 2013
Print Thread
99 Merc 150 EFI 2 Stroke - Hard to start when warm #13634354 07/17/20 07:08 PM
Joined: May 2006
Posts: 452
R
Ringer1 Offline OP
Angler
OP Offline
Angler
R
Joined: May 2006
Posts: 452
The motor will start just fine at the ramp. But once it's warm I have to tilt the motor all the way up and throw it into gear when it seems like it wants to start.

I've changed the spark plugs and the fuel filter. The water separator is next. But I wanted to see what you guys thought it could be. TIA

Re: 99 Merc 150 EFI 2 Stroke - Hard to start when warm [Re: Ringer1] #13634541 07/17/20 09:15 PM
Joined: Jun 2004
Posts: 1,509
O
OPTI Offline
Extreme Angler
Offline
Extreme Angler
O
Joined: Jun 2004
Posts: 1,509
Sounds like the the ECM thinks it is still cold which is controlled by the port head temp sensor could be bad or make sure it is not unplugged .....OPTI

Re: 99 Merc 150 EFI 2 Stroke - Hard to start when warm [Re: OPTI] #13634680 07/17/20 11:36 PM
Joined: May 2006
Posts: 452
R
Ringer1 Offline OP
Angler
OP Offline
Angler
R
Joined: May 2006
Posts: 452
Originally Posted by OPTI
Sounds like the the ECM thinks it is still cold which is controlled by the port head temp sensor could be bad or make sure it is not unplugged .....OPTI





I'll pull up the schematics and see if I can find the sensor. Thank you for the response.

Re: 99 Merc 150 EFI 2 Stroke - Hard to start when warm [Re: OPTI] #13662261 08/10/20 01:22 AM
Joined: May 2006
Posts: 452
R
Ringer1 Offline OP
Angler
OP Offline
Angler
R
Joined: May 2006
Posts: 452
This the only temp sensor I can find on the schematic. I don’t see anything that says “port temperature sensor”. Is this what your talking about?

Temp sensor

Re: 99 Merc 150 EFI 2 Stroke - Hard to start when warm [Re: Ringer1] #13663295 08/10/20 09:29 PM
Joined: Jun 2004
Posts: 1,509
O
OPTI Offline
Extreme Angler
Offline
Extreme Angler
O
Joined: Jun 2004
Posts: 1,509
The picture your asking about is the manifold air temp sensor. The part # for the sensor Iam talking about is 13536 A14 if you go into Crowley Marine and enter this # it will show a picture of sensor It is the port cylinder head temp sensor The starboard sensor is just for the warning horn. .... OPTI

Last edited by OPTI; 08/11/20 09:52 PM.
Re: 99 Merc 150 EFI 2 Stroke - Hard to start when warm [Re: OPTI] #13666138 08/13/20 02:54 AM
Joined: May 2006
Posts: 452
R
Ringer1 Offline OP
Angler
OP Offline
Angler
R
Joined: May 2006
Posts: 452
Perfect!!! Thanks OPTI!!!!

Re: 99 Merc 150 EFI 2 Stroke - Hard to start when warm [Re: Ringer1] #13666984 08/13/20 10:43 PM
Joined: Jun 2004
Posts: 1,509
O
OPTI Offline
Extreme Angler
Offline
Extreme Angler
O
Joined: Jun 2004
Posts: 1,509
No problem

Previous Thread
Index
Next Thread

© 1998-2022 OUTDOOR SITES NETWORK all rights reserved USA and Worldwide
Powered by UBB.threads™ PHP Forum Software 7.7.3