tech help please?

[tommcat]

you wouldnt have a list of DTCs that you could PM or fax me would you. i'd like to have a list of the possible codes and descriptions for future reference.
thanks

[tommcat]

ok, a little more info now that i'm at my shop and checked it again.
on the no start, i have 40 PSI of fuel while cranking. so fuel is not an issue. one odd thing i did notice is that my check engine light is off while it's cranking but no starting, eventually the light comes on and as soon as it does the engine fires right up.

[JimN]

OK, go back in the posts and look for the paperclip method of checking your codes. First, go through the boat and make sure the battery terminals are clean and tight, the grounds on the motor are tight and the sensors are plugged in fully. Also, check the knock sensor and make sure the wire is attached. Also, if you have the fuel gauge with the relief valve and clear tube attached, take a fuel sample. While you're at it, look on the tank and see if the lever on the fuel shutoff is in line with the hose.

Also, even if you didn't notice it, if the motor overheated, the wires with the two wire ECT may have melted and come in contact with the intake manifold or each other. These wires are yellow and black. The one wire sensor will have no bearing on how the motor runs.

The codes for marine engines of your vintage are:
DTC 14= ECT SENSOR CIRCUIT LOW (ECT IS ENGINE COOLANT TEMPERATURE SENSOR)
DTC 15= ECT SENSOR CIRCUIT HIGH
DTC 21= TPS CIRCUIT HIGH (TPS IS THROTTLE POSITION SENSOR)
DTC 22= TPS CIRCUIT LOW
DTC 33= MAP SENSOR LOW (MAP IS MANIFOLD ABSOLUTE PRESSURE)
DTC 34= MAP SENSOR HIGH
DTC 41= IC CIRCUIT OPEN IC (IC IS IGNITION CIRCUIT)
DTC 42= IC CIRCUIT GROUNDED IC OPEN OR GROUNDED BYPASS
DTC 43= KS SYSTEM CONTINUOUS KNOCK (KS IS KNOCK SENSOR)
DTC 44= KS SYSTEM NO KNOCK
DTC 51= CALIBRATION MEMORY FAILURE
DTC 52= EEPROM FAILURE (EEPROM IS ERASABLE ELECTRONICALLY PROGRAMMABLE READ ONLY MEMORY)

Now that you know what the codes are, it may help, but I would do a wiggle test on any ground wires or anyplace where wires are combined. If you grab the main harness and move it while the motor is running, you may notice a difference in how the motor runs. If you do, you'll need to investigate and this may require removing the plastic wireloom from the harness. This absolutely needs to go back on!

[tommcat]

here's a little update. the no start problem is diagnosed. the ignition feed off the back of the ign switch has an intermittent open. no power feed to the ignition system, jump the circuit and it starts every time.

now i need to get it back in the water to find my loss of power problem, if it's still there.

[tommcat]

finally got in the water over the weekend and got some hours on it. the power loss problem did happen again intermittently.
this time i had my fuel pressure gauge with me and it was dropping to 20-25 psi while the problem was happening. got it in the shop this morning and pulled the fuel tank. i found some bugs and other floaties in there. also check the screen in the fuel pump and found some black goo in there.
cleaned everything up and hope to retest this week. i'm just about 100% positive that was my whole issue.

[JimN]

That sounds like the problem. Make sure you clear out the fuel pickup tube completely. There can be stuff left over that isn't easily visible. Look at the anti-siphon valve, too. That may have some on or in it.

[tommcat]

Originally Posted by JimN

That sounds like the problem. Make sure you clear out the fuel pickup tube completely. There can be stuff left over that isn't easily visible. Look at the anti-siphon valve, too. That may have some on or in it.

i blew through the pick up tube, it's perfectly clean now.
where is the anti siphon valve located?

if it does it again i have the tool in the boat to pull the fuel pump and clean the screen again. just in case there was some stuff in the line. i can pull the pump out in about 2 minutes. i can get the tank out in about 10 if need be also.

[JimN]

The anti-siphon tube is the first thing the gas goes through after the pickup tube. It may be part of the gas shut-off valve.

[tommcat]

Originally Posted by JimN

The anti-siphon tube is the first thing the gas goes through after the pickup tube. It may be part of the gas shut-off valve.

ahh. that part was all clear, from the pick up screen right to where the rubber hose hooks to it.
thanks for the input jim