can anyone help my 93 classic has just developed a massive hesitation while coming on boost even the rev guage drops to 0 ??? no CEL had service 2 months ago cars been running fine since then anyone any ideas???

 

Check coil packs first. Take them out see if they''re cracked or signs of tracking to earth.

 

Could be tge maf sensor. They cause all sorts of running issues without throwing up a cel code.

 

Lambda

 

Rev guage dropping to 0 would suggest a short or earthing problem.

 

Right folks checked all coilpacks one was cracked changed that and went for a blast all was fine for the first 5mins then started again also when i was just crusing the CEL light came on then went off ? Also changed the maf for a mates working one, Definately not that as problems still there?

 

Why u think its the lambda?

 

From your description of the fault, mine was exactly the same, and you have changed everything else have you not?

The lambda can throw a code, but it can also be faulty without throwing a code, mine never gave any code at all.

Got one for £56 from a local motor factor, job done

 

Check what the fault code is and go from there first. If still not sure, I would recheck the coil packs and also the ignitor/amplifier. I suspect they are linked to the rev counter dropping down also.

The ecu has a specific earth controlling the ignition side so check the ecu earth supplies also.

 

Map sensor or line....I get something similar when my MAP line blows off!