So doing a car that was running great and swapped to some lpe injectors. Car didnt run no idle I mean it was crap on lpe tables that came with it. So reached out to Nostrum as lpe is useless and dustin an engineer/calibrator looked at a log and took the tune and changed up around 15 tables. Now we got somewhere car starts idles black smoke gone working good enough to go drive and log. So after adjusting and part throttle work I told him try a wot on it. Car goes a little lean .88 and 4800 rpm the pump pressure go from commanded 2900 to 3200 back to 2900 then 5400 it slams 4200 psi and locks the injectors up and huge lean spike as expected. So I send the log to dustin and trys to tell me its due to the 38 percent lobe on the cam and 32 percent axis I had on the pump. I see big tuners that leave that table stock. On this one I had forgot it had a 38 lobe and put the 32 percent axis as I told him some car specs.
Now I know that is not the issue as I said many dont even bother to touch it on cars with cams Ive seen tunes from howard and many other cars I have re tuned for people that (good) known tuners have done. So now scratching my head on what can cause such a spike on a pump that I was commanding 2900 and had 3200 in the max pressure tables. I have had conversations with Bob owner of FIC and he told me how many sets of injectors he has got back with the springs broken in them from people commanding 3400 plus psi to them. So I always in my tunes lower things trying to be proactive as there is no reason for them to over pressure.
This is the first time I have ever seen it this bad. Some cars I have seen it hit 3200 if injectors got near limits and recovered it can go over but always goes back to commanded.
Has anyone seen it so bad it makes the injectors lock up like this? I can post a log but it is like a dead fuel cut like dfco almost when off throttle big spike so I know they are no longer working though at 3.3 ms. Hoping someone has some idea of why this can happen.
Thanks