A Tale of woe.... Our customer has just bought this from an auction and discovered that it wont rev above around 2500 RPM as its in limp home mode. Diag test revealed no data from crank sensor as it was disconnected. If we reconnect it but the engine will then not start. The only fault code relates to he crank sensor which is currently disconnected.

It looks like the engine has been out and may be reconditioned. We've checked cam timing etc and all seems well.

I've scoped the cam and crank sensors. The crank sensor was disconnected to enable tests when the engine was running. The scope pattern remains the same when it is connected.

I'm stumped with this one. There appears to be no TDC reference point on the crank pick up which confuses me slightly.

Any ideas?

hi peter,check for end float in the crank,the thrust washers are made of chocolate!hac one similar with about 15mm float keith

End float has been checked and is within spec. As I say, it does look like the engine has been reconditioned and I'm sure the clue lies therein. If we either disconnect the crank sensor plug or leave it plugged in but not located, the engine starts and runs fine. Its only when the sensor is picking up a signal that it wont start. If the crank has no TDC reference how does the ECU know that something is wrong and prevent it from starting? It must only use this signal as a speed reference and not timing....

Does the engine number on the V5 match the engine?

Mark

Mark, we have looked for an engine code and number but haven't found it yet. Will have another look later.