Posted by hemimech [172.68.59.27] on Thursday, August 16, 2018 at 14:48:36 :
In Reply to: 1990 dodge tbi rough idle and stalling issue posted by 1990dodge [162.158.63.175] on Wednesday, August 15, 2018 at 19:53:46 :
If it's approaching 200k miles it's possible the timing chain has jumped a tooth or two causing the camshaft to be retarded. If your truck has the TBI then it should have the cranksensor on the passenger side near the back of the right cylinder head sandwiched between the engine block & transmission. If this is the case then the ignition timing will still check ok (to a certain point) because it's fired off the flexplate tone wheel & not the distributor orientation. If the chain has jumped a simple compression check should show it's low on all cylinders. Also a cylinder leakdown at TDC will usually be high due to a late closing exhaust valve.