I have a 95 psd with 160/80s, adrenaline hpop, irate e fuel, and a s366 turbo. Also added head studs, valve springs and push rods as supporting mods. I have a hydra with tony wildman tunes and with the more aggressive tunes towing, street, extreme I get what I believe is preignition. Rpms drop 300-400 rpm and jump back up almost like it's trying to shift gears but can't stay in that gear. Also get the typical spark knock/preignition sound you get with gas vehicle. It happens when the vehicle is under load usually between 2000-2200rpm. Sometimes I can throttle past it and it will go away. It doesn't do it in the stock tune setting. I have an ae scan tool but haven't had a chance to data log and any helpful direction as to what I'm looking for to confirm my diagnosis would be great and if any has dealt with this how did you fix it?

 

When it bows and gains are you talking at idle or driving?

 

Driving, The truck seems to idle fine. It seems more under acceleration at around 25-30 mph and get worse from there. Which I believe is around where the 2-3 shift should be?

 

Got some time with the scan tool on it. No misfires showing on the cylinder count but I don't have enough experience with this software to know weather it would even if there was a misfire? Icp goes to 2700 wot and duty cycle never goes above 37-38% so I'm assuming it's not an oil supply problem. Seeing as it only does it in higher tunes. I might try some other companies tunes and see if it changes although from what I've read wild man seems to be one the better tunes supposedly? Also if this is preignition wouldn't a meth injection kit help if not solve this issue? Anyone have and experience with water meth injection on their trucks?

 

I doubt its preignition. Tony's tune are aggressive to say the least but I don't think they are your problem. I'm thinking you have a auto problem but don't know.

 

By definition, it's impossible to get pre-ignition in a diesel..... Nothing to ignite until the diesel is injected.

Methanol CAN cause pre-ignition, since the methanol is a flammable gas that can ignite within the cylinders before TDC....

Sounds to me like you've got to much timing, or your just not used to hearing a diesel with lots of timing advance.