Timing chain?
I strongly suspect the vehicle has a timing chain issue,however Id like a little info on what Im seeing. Ive compared my wave form with the one we have here(thanks ATG) and on other sites and it looks the same.
However I have these blips(sawtooth?) in my camshaft trace(red), and Id like to know if that is indicative of a chain issue,or maybe thats simply my equipment.
I notice that the blips also appear in the yellow trace, as elevated pulses. I more suspect them to be some kind of bleedover from the ignition.
Hi Rudy, The one you posted looks good. Is this your problem car?
Stephen is correct — both traces are affected. What do you use as a scope ground? And how healthy are ECM grounds relative to battery negative?
Ok guys I was just checking things the easy way before getting too intrusive. I certainly didn't want to chase my tail on stray, ghost images. After Stephen posted his thoughts,I moved on to my next step, checked back pressure. 10+ psi at WOT. Safe to say I found my issue(although the engine still rattles like a mother) BTW my scope lead was attached to battery ground. Ive never had an image…
Those are coils methinks.
2001 Ford with bad chains AND bad converters.....how did you get one of our customers cars Rudy? LOL - Happy Weekend Vato.
When a 4.0L SOHC stops "Rattling", only then is it cause for concern ;)
That is just a set of loads being turned on and off, coils or injectors. Seeing this type of impact is very common when the scope is set up to display fine detail.
This would be a good one to look at fuel trim on. A clogged cat on one side will cause trim to be skewed in opposite directions bank to bank.
Bob- Yes, Ive seen that quite often. In this case bank 2 was -25%(stft), however bank 1 was only slightly off at +7% to +10%. Ive seen similar readings when one bank is out of time.