Originally Posted by chrislandy
Right, dragging the thread from the depths but I've just got back from France testing the boat.
Engine fine when started from cold
When coldish i.e. when the guage isn't registering it won't rev (in or out of gear) past 2600
When warm, you can barely get it over a fast idle @ 1200rpm or 20kph
For example, when coldish I had it up to 2600rpm / 40kph and tried to go faster, it either carried on the same or "choked" and bogged down.
I've changed the CTS at the rear under the manifold
The temp guage when hot is 62degC or about 145degF
I've cleaned all the earths at the front and the rear of the engine
I'm getting 5v at the MAP and TPS loom power
I've taken off the fuel pipe and blown it through (no debris of blockages)
I've taken off the fuel pump and checked for blockages (none)
It took a while to work out why the engine light wasn't coming on, MC UK put a recon engine in before we bought it and had cut the wire by the looks of it as the white connector at the back of the engine didn't have a wire coming from it (never did by the looks of it as the bungs were in both terminals) and the pink/black or pink/blue wire was just floating around the engine bay!
Anyway now the engine light works, the ECU throws up codes 22 and 33
22 - TPS too low?
33 - MAP too high?
Are these both past their best? I didn't manage to get a voltage reading from them though as I only got the engine light working 2hrs before I had to leave.
IIRC, those sensors share their ground- check the ground connections at their attachment points on the block, clean and tighten the battery cables/posts and see if it improves.
A diagnostic computer has a screen that shows the voltage, as seen by the ECM. This is a critical piece of info and can't be found anywhere else. I found a few that had flaky grounds- measured anywhere on the engine or at the battery, it looked fine but the ECM didn't agree with that.
Your measurement of 5VDC at the sensors is only part of the story- you need to measure from the ground wire in the harness to the battery negative post. Not the cable end, not the block, but the battery post. All voltage references should be made with the meter connected to the negative battery post. Don't open the wire loom and strip the tape unless you see evidence of melting from an overheat. If you see melted wire loom and wires, your harness needs to be repaired and this will cause many problems.
Unplug the TPS and see if it runs better.