Loss Of Power At 60 - 70,juddering All The Time

[Guest joe34]

hi all

i have had my car in the garage for the past two weeks and cannot find the source of the problem,i have had all spark plugs changed and a diagnostic check which came back saying the sensor in the exhaust was at fault i had it replaced and it came up fine but the problem did not clear it just got worse,i think he tried a new fuel pump but to no evail,the mechanic said everything he tries does not work and it has to go back in this week,does anyone have any idea what can be causing it as i am getting close to pulling my hair out,it does not lose power all the time but does judder about a lot,sometimes it drives like a dream then suddenly it is like driving over a cattle grid,it now does not go over 60,help :lol:

 

thanks

 

joe

[Ivor_E_Tower]

Won't go over 60 - is it road speed related, or if you rev the engine at rest in neutral will it reach the red line? Is it smooth when under no load, or only when driving? Sounds a hard one to diagnose. I would almost suggest disconnecting one spark plug at a time and seeing if this replicates the rough running, but this may damage the cat - that's complicated modern electronics etc for you! Anyone else got any ideas? Seems strange that no fault codes are logged if you cannot go over 60 - crankshaft position sensor faulty?

[Guest nimrod]

If it wasnt for the fact that this is a petrol engine I would say MAF fault! but as its petrol try relay 30? IIRC this one can cause running and starting problems! its been the cause of a few peoples problems!

[Guest joe34]

hi

i went out and checked the revs while stationary and it hit 45000 max and would not go any higher and when it is shuddering the rev counter goes up in jerks,i took the relay 30 out and reseated it as i dont have a spare but it has made no difference but i will try and get one tommorrow

 

joe

[Guest nimrod]

hi

i went out and checked the revs while stationary and it hit 45000 max and would not go any higher

For the sake of your engine I do hope thats a miss type! 45000 rmp! :lol:

[Ivor_E_Tower]

Dunno 'bout that - if it can reach 45000 :lol: , there can't be much wrong with it!

 

Seriously, if it won't go above 4500, there is definitely something amiss, and a technician should be able to start tracking a few things down.

[Topbloke]

just a thought that it could be a partialy blocked exhaust ( cat collapsed) you could try seing how much presure there is at the tail pipe (might be a little hot though ) just on tickover there should be enough pressure after a little while to push your hand off if you dont fancy that run it into the garage and get them to do an emmision's check should be about right as you have had a new sensor it they do a full cat test that will confirm any amount of problems ,weak running (air leak ) rich mixture (temp sensor ) any chance off some feed back as its good to know and store in the memory bank

[Guest joe34]

I only got the MOT 2 weeks ago & it passed they said it had passed on everything it's going back into the garage again on Tue guy has been really good & luckily not charging me anything till he knows what is causing it, but so far it has had everyone stumped so hopefully I will get some clues on here, I only bought the car in private sale 5 months ago as we had another baby & needed a people carrier to fit all the kids in reviews of galaxy were good but so far this one is costing us a fortune, ran great at the start, as soon as I know what the problem is I will leave some feedback letting you all know, in the meantime any suggestions as to what it could be are appreciated

 

Thanks

Joe

[Nige F]

Have had exactly the same problem appear over the weekend, on top of everything else that has gone wrong with the car over the last week or so (see other posts).

 

Disconnected the MAF this morning and the car runs fine, revs freely all the way to the red now. Reconnected it to double check and the problem came back, so off to the local dealers to increase their profits even more!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

Not sure if the 20L has a MAF, but it has got to be worth a try.

[Topbloke]

you should have recieved an emmisions pass sheet that would give the readings it you did not ask tyhem for it was the car running okay after you picked it up (silly question) the sensor will not cause a missfire per sey but it could tell the ecu to lean of also if the sensor was us for how long ! this could also cause a cat problem . keep me posted please

[Guest joe34]

hi all

problem has now been solved,it was the airflow sensor that was faulty as he took one out of a galaxy that was working and it made that one unstable and misfire but my car was still the same ? :P i got told that this part does not show up in the diagnostic test,so i then new i had two faulty parts which cause the same problem, he changed the ht lead and my car is now running superbly,two faults in the one cause lots of problems

 

 

thanks for all your help

 

joe :rolleyes: