Challenger 2000 240 EFI Won't idle - Bad TPS?

[nenikol23]

I have a 2000 Challenger 2000 with the EFI 240 M1 (round flywheel cover)

I have had the boat for 8 months and never got to get it going (got busy in February and never pursued the to diagnose, but now I am determined to either fix it or sell it as is)

There is more history on what was done on it before I bought it, as well as all the symptoms and troubles I have with it at this post:
2000 Challenger 2000 240 Merc Stalls above 2800 RPM


Now I am at a point of testing/adjusting the TPS. I recall when I got the boat, I was looking thru the hull inspecting for random obvious issues like unplugged things, brittle/cracked hoses etc. At the time, I found the TPS loose, so I had just tightened the two bolts holding it (not knowing how it works and what it does). I am now reading the procedure to adjust the TPS. With the Port temp sensor connectors unplugged, throttle all the way back, loosen the TPS turn it at the most clockwise position. I don’t have the tool that is used in the manual so I shaved off the wires a little to get the probes from the multimeter. Blue wire is + / Brown wire is -
According to the manual, move the sensor counterclockwise until you read 0.2-0.3 volts. I am able to get it to 0.125v and the slightest movement in the counterclockwise direction will bring me to 1.2v. Cannot get anything in between. Is that a solid proof that the TPS is bad?

With the TPS in the most clockwise position, the boat will start and shut off after less than 1 second. If I move the TPS somewhere mid travel the boat will start and run for 1-2 seconds. Also in this position, if I hold the key to cranking position the engine will keep running until I let go of the key. I have not tried longer than 10 seconds. But this pattern is definitely not a coincidence as I am able to reproduce it over and over again.

So final question, am I safe to get a TPS and hope that solves it?

 

[Tim75]

I have a 2000 Challenger 2000 with the EFI 240 M1 (round flywheel cover)

I have had the boat for 8 months and never got to get it going (got busy in February and never pursued the to diagnose, but now I am determined to either fix it or sell it as is)

There is more history on what was done on it before I bought it, as well as all the symptoms and troubles I have with it at this post:
2000 Challenger 2000 240 Merc Stalls above 2800 RPM


Now I am at a point of testing/adjusting the TPS. I recall when I got the boat, I was looking thru the hull inspecting for random obvious issues like unplugged things, brittle/cracked hoses etc. At the time, I found the TPS loose, so I had just tightened the two bolts holding it (not knowing how it works and what it does). I am now reading the procedure to adjust the TPS. With the Port temp sensor connectors unplugged, throttle all the way back, loosen the TPS turn it at the most clockwise position. I don’t have the tool that is used in the manual so I shaved off the wires a little to get the probes from the multimeter. Blue wire is + / Brown wire is -
According to the manual, move the sensor counterclockwise until you read 0.2-0.3 volts. I am able to get it to 0.125v and the slightest movement in the counterclockwise direction will bring me to 1.2v. Cannot get anything in between. Is that a solid proof that the TPS is bad?

With the TPS in the most clockwise position, the boat will start and shut off after less than 1 second. If I move the TPS somewhere mid travel the boat will start and run for 1-2 seconds. Also in this position, if I hold the key to cranking position the engine will keep running until I let go of the key. I have not tried longer than 10 seconds. But this pattern is definitely not a coincidence as I am able to reproduce it over and over again.

So final question, am I safe to get a TPS and hope that solves it?

Set a catch can under the vst. Turn key to run. open vst drain screw. How much fuel flows? A couple of seconds or continuously? If only seconds, your vst inlet float needle is suspect. It may be stuck. Only allows enough fuel to run engine for seconds. Check vst pressure. 35-37psi, engine on or off. When you turn key to OFF, pressure should drop slowly. 5 seconds to 30 seconds.

 

[nenikol23]

Set a catch can under the vst. Turn key to run. open vst drain screw. How much fuel flows? A couple of seconds or continuously? If only seconds, your vst inlet float needle is suspect. It may be stuck. Only allows enough fuel to run engine for seconds. Check vst pressure. 35-37psi, engine on or off. When you turn key to OFF, pressure should drop slowly. 5 seconds to 30 seconds.

Hey Tim,

Performed the test as you suggested. A lot of fuel will flow for a while with the key on. You can see the video I filmed HERE.

I also performed the "Electric Fuel Pump Voltage Test" as per service manual (p.224-226)
RESULTS:
- BLACK Meter Lead to Engine Ground; RED Meter Lead to (+) terminal of fuel pump = 12.45 Volts
- (ignition key to OFF) BLACK Meter Lead to Engine Ground; RED Meter Lead to (–) terminal of fuel pump = 12.45 Volts
- (ignition key to ON) BLACK Meter Lead to Engine Ground; RED Meter Lead to (–) terminal of fuel pump = 2.2 Volts (Here the manual suggest it should be less than 1.5 volts...)
- (engine being cranked) BLACK Meter Lead to Engine Ground; RED Meter Lead to (–) terminal of fuel pump = 2.2 Volts (Manual also suggest it should be less than 1.5 volts...)

I then did the following as per manual: Disconnect BLACK/RED wire to negative terminal on electric fuel pump. Connect a ground jumper wire from negative pump terminal to a good engine ground.
RESULT --- I could hear the Electric fuel pump for the first time. Tested pressure while on at the shredder valve and it was 37psi. As soon as the "bypassed ground" is removed the pump stops and the pressure goes to 0psi instantly.

My assumptions: Pump unable to hold pressure & bad ground. Are they related?

One more thing, after realizing that the Fuel pump seems to have a bad ground we attempted to start the engine with the additional ground wire, out of 30 attempts, only once were we able to get the engine to run more than 1 second, give it a little throttle (kept it below 1200 rpm with the water hose on)

What are your thoughts?

 

[Tim75]

Hey Tim,

Performed the test as you suggested. A lot of fuel will flow for a while with the key on. You can see the video I filmed HERE.

I also performed the "Electric Fuel Pump Voltage Test" as per service manual (p.224-226)
RESULTS:
- BLACK Meter Lead to Engine Ground; RED Meter Lead to (+) terminal of fuel pump = 12.45 Volts
- (ignition key to OFF) BLACK Meter Lead to Engine Ground; RED Meter Lead to (–) terminal of fuel pump = 12.45 Volts
- (ignition key to ON) BLACK Meter Lead to Engine Ground; RED Meter Lead to (–) terminal of fuel pump = 2.2 Volts (Here the manual suggest it should be less than 1.5 volts...)
- (engine being cranked) BLACK Meter Lead to Engine Ground; RED Meter Lead to (–) terminal of fuel pump = 2.2 Volts (Manual also suggest it should be less than 1.5 volts...)

I then did the following as per manual: Disconnect BLACK/RED wire to negative terminal on electric fuel pump. Connect a ground jumper wire from negative pump terminal to a good engine ground.
RESULT --- I could hear the Electric fuel pump for the first time. Tested pressure while on at the shredder valve and it was 37psi. As soon as the "bypassed ground" is removed the pump stops and the pressure goes to 0psi instantly.

My assumptions: Pump unable to hold pressure & bad ground. Are they related?

One more thing, after realizing that the Fuel pump seems to have a bad ground we attempted to start the engine with the additional ground wire, out of 30 attempts, only once were we able to get the engine to run more than 1 second, give it a little throttle (kept it below 1200 rpm with the water hose on)

What are your thoughts?

Definitely NOT a stuck inlet needle.

Bad ground: start checking wires. Trace back from the vst. Check ground wires. There are at least 3. Check inside the round connector clipped into a bracket starboard side, near front of engine. Be careful of that connector. Many wires. No green connections allowed.

Pressure dropping: more indicative of one or more leaking injectors which can cause a "flooded" condition and hard to start. Kind of a pain to get them out, but one of the best things I ever did for my boat. $120 for service and calibration. $750 for a new set from Merc. Order the 3 gaskets prior.

 

[nenikol23]

Have started to trace back grounds and will work on that more today.

I also removed plugs (brand new, replaced weeks ago) to check for spark and compression. All get spark. Interesting thing is the condition of the plugs. Plugs on the port side were all black, while plugs on the starboard side were all clean. See picture below.

Compression: 135psi on all cylinders except no.1 on starboard side, 125psi.

I have no problem removing the injectors and getting them serviced/replaced if that will fix the problem. Any other injector tests I can do to narrow it down to injectors before removing them?

 

[nenikol23]

Was getting ready to removing stuff to get to the injectors when I got the idea to test the TPS in the most counterclockwise position. With this done, boat would start and run for a second longer than before, time over time.

Was still bugging down unless shifted in gear and some throttle applied...So I was messing around with different stuff until I decided to pull the plugs again to see how they look after all the starting/stalling.

Most plugs looked "wet" except the middle cylinder on the port side. That one has a completely white tip, see pic below. What can cause this? What's so different with this cylinder vs the others? These are new plugs from a few weeks ago, boat never actually ran with these plugs yet.

 

[cbjustDOOit]

white deposits are signs of a burned spark plug that is running too hot. Causes can include the engine overheating, incorrect spark plug heat range, a loose spark plug, incorrect ignition timing or too lean of an air/fuel mixture.

 

[nenikol23]

Definitely NOT a stuck inlet needle.

Bad ground: start checking wires. Trace back from the vst. Check ground wires. There are at least 3. Check inside the round connector clipped into a bracket starboard side, near front of engine. Be careful of that connector. Many wires. No green connections allowed.

Pressure dropping: more indicative of one or more leaking injectors which can cause a "flooded" condition and hard to start. Kind of a pain to get them out, but one of the best things I ever did for my boat. $120 for service and calibration. $750 for a new set from Merc. Order the 3 gaskets prior.

@Tim75 Which 3 gaskets are you referring to? VST + Intake cover + intake to engine (the one with 5 sections) ?

Took it all apart, waiting to get injectors serviced...

 

[Tim75]

@Tim75 Which 3 gaskets are you referring to? VST + Intake cover + intake to engine (the one with 5 sections) ?

Took it all apart, waiting to get injectors serviced...

3 gaskets between throttle body.

Take a close look at the reeds while you can.

 

[nenikol23]

@Tim75

The only gasket the Merc parts dealer in my area can see is this one...

EDIT *** The gasket is sold as one piece and has to be cut

 

[Tim75]

@Tim75

The only gasket the Merc parts dealer in my area can see is this one...

EDIT *** The gasket is sold as one piece and has to be cut

View attachment 51268

That is the one. As it says- it gets cut apart to install. As you take the throttle body off, it will be 3 gaskets.

 

[nenikol23]

I had the injectors tested and it looks like I have 1/6 injectors that is actually working properly.
2 are completely "dead"
3 have improper flow rates/spray patterns.

Now I gotta find a set of injectors that will not cost me more than what I paid the boat lol

 

[Tim75]

I had the injectors tested and it looks like I have 1/6 injectors that is actually working properly.
2 are completely "dead"
3 have improper flow rates/spray patterns.

Now I gotta find a set of injectors that will not cost me more than what I paid the boat lol

My shop was able to rebuild mine.........

Your service shop may know what else uses these inj. Entire throttle bodies appear on ebay.

 

[novafreak69]

Read this post hoping to find a quick fix lol...


I have just acquired a 2000 Challenger 2000 with the same engine and somewhat same issue... It is hard to start... I have been successful starting it by turning the wheel hard left or right... then it idles a bit rough and smokes quite a bit. after running the boat for a bit the smoke goes away... but the idle is still horrible... it dies while trying to maneuver the boat at idle...

I have replaced Spark Plugs and the Temp sensor in the port side Cylinder head.

From what I have been reading, I guess check the TPS is next?

and advice on next steps would be greatly appreciated.

 

[Tim75]

Read this post hoping to find a quick fix lol...


I have just acquired a 2000 Challenger 2000 with the same engine and somewhat same issue... It is hard to start... I have been successful starting it by turning the wheel hard left or right... then it idles a bit rough and smokes quite a bit. after running the boat for a bit the smoke goes away... but the idle is still horrible... it dies while trying to maneuver the boat at idle...

I have replaced Spark Plugs and the Temp sensor in the port side Cylinder head.

From what I have been reading, I guess check the TPS is next?

and advice on next steps would be greatly appreciated.

What is your in-the-water RPM? Should be 1100-1200 rpm. If it's too low, it may be hard to start in the water.

Check the: fuel pressure.
TPS.
spark x6.
Compression.
Wires from trigger coming out from under the flywheel. (on bracket, aft of flywheel.)

 

[novafreak69]

What is your in-the-water RPM? Should be 1100-1200 rpm. If it's too low, it may be hard to start in the water.

Check the: fuel pressure.
TPS.
spark x6.
Compression.
Wires from trigger coming out from under the flywheel. (on bracket, aft of flywheel.)

YES... That is exactly what is going on. It starts every time in the shop out of the water.... but as soon as you put it in the water.... it does not want to start.... and crappy idle... OK.. going to start checking these things today, I have the manual. Is that the order to check them in?

 

[novafreak69]

TPS Sensor wires to test....Is it the two outside wires on the connector? Pins A and C?

 

[Tim75]

TPS Sensor wires to test....Is it the two outside wires on the connector? Pins A and C?

Center wire and one outside wire. Don't remember which.

 

[novafreak69]

Center wire and one outside wire. Don't remember which.

Yep I figured it out... and the TPS is Bad. It has a bad spot... it goes from 0v to .550v... nothing in between... so now I am on the search for a TPS Sensor... and WOW... they certainly are proud of them. After I get the new TPS and on there adjusted I will move on....will check compression also... but I doubt its a problem... boat runs 55-60 MPH under WOT.

 

[novafreak69]

Just an FYI the TPS sensor new number is 14851T03 ... and yep... Still $575 OOF....

 

[novafreak69]

and just another question... how can I tell what My RPM is? I don't have a tachometer...

 

[Tim75]

and just another question... how can I tell what My RPM is? I don't have a tachometer...

Sounds like a new tach is in your future. I replaced my 2" SeaDoo tach with a standard size unit for $60.

There are throttle bodies that show up on ebay with tps (used) and injectors for $200. I bought an old style tps with the round connector for $125. 5 years ago. 10 minutes with a soldering gun and that unit is still working fine. If you can find a dealer with old stock.

 

[nenikol23]

@novafreak69 Like Tim75 said. I just bought two throttle bodies (different part numbers for throttle bodies but same part numbers for injectors) I needed the injectors. Turned out my TPS was bad too, very very hard to turn. The throttle bodies came with TPS sensors on them, took one of them, chopped the wires (different connector) and just used some waterproof connectors with shrink tubes. All set for under $300 (set of injectors and TPS)

@Tim75 --> After replacing my injectors (got them tested before putting them in, all good) replaced and adjusted TPS, installed all new gaskets and seals. Boat starts up and runs every-time however the RPM will sometimes be 1000 rpm, sometimes 3000 rpm...Tried to adjust the idle screw but still erratic every time I start it. Suggestions?

 

[novafreak69]

@novafreak69 Like Tim75 said. I just bought two throttle bodies (different part numbers for throttle bodies but same part numbers for injectors) I needed the injectors. Turned out my TPS was bad too, very very hard to turn. The throttle bodies came with TPS sensors on them, took one of them, chopped the wires (different connector) and just used some waterproof connectors with shrink tubes. All set for under $300 (set of injectors and TPS)

@Tim75 --> After replacing my injectors (got them tested before putting them in, all good) replaced and adjusted TPS, installed all new gaskets and seals. Boat starts up and runs every-time however the RPM will sometimes be 1000 rpm, sometimes 3000 rpm...Tried to adjust the idle screw but still erratic every time I start it. Suggestions?

I just looked on Ebay and nothing... i am looking to get back on the water nest week :/

 

[novafreak69]

@novafreak69 Like Tim75 said. I just bought two throttle bodies (different part numbers for throttle bodies but same part numbers for injectors) I needed the injectors. Turned out my TPS was bad too, very very hard to turn. The throttle bodies came with TPS sensors on them, took one of them, chopped the wires (different connector) and just used some waterproof connectors with shrink tubes. All set for under $300 (set of injectors and TPS)

@Tim75 --> After replacing my injectors (got them tested before putting them in, all good) replaced and adjusted TPS, installed all new gaskets and seals. Boat starts up and runs every-time however the RPM will sometimes be 1000 rpm, sometimes 3000 rpm...Tried to adjust the idle screw but still erratic every time I start it. Suggestions?

you have the part numbers of the throttle bodies?