haltechsupra
New member
- Joined
- Jun 22, 2004
- Location
- Texas
Bench diagnosis, better than bench racing... What had happened was..... alternator and map sensor intermittent. Alternator drops voltage at wot, to battery voltage, nukes only number 4 piston.. Why? Map sensor got alcohol in it, re plumbed vacuum hose to top of intake instead of bottom. Alternator is broken, but why always number four, here's a few theories. I first thought it was just one issue. It seems to be two. Heat and fuel. Back of head is quite a bit hotter. Then there's the firing order, 1-3-4-2. So fuel comes in the fuel rail from the front hitting cylinder one first and cylinder 4 last. Well, in the firing order if there's any instance where fuel flow is compromised, number four always takes it in the back. The reason i think that is , because on firing order 1342, cylinders 3 and 4 being side by side and fed one right after the other at the tail end of the fuel rail, the fuel rail cannot simply maintain enough pressure and flow for cylinder four, after firing cylinder 3 right next to it. Upgrade fuel rail to twin feed at front and back? Wonder if the fuel rail capacity/diameter is a direct relation to this as well? Fuel rail isolator?
Infra red gun on front of head 210, back of head 245 degrees with heater core bypassed. Rerouted coolant hose from water pump to back of head. Plugged hose from water pump around back of block(heatercore hose) , and ran heater core hose out of head back to thermostat housing. Drilled and tapped. Now temps at back of head are 20 degrees cooler than front, so i will put a restrictor in hose coming from back of head, so thermostat can work, more like it should.Idea from LS1/x steam ports.
Infra red gun on front of head 210, back of head 245 degrees with heater core bypassed. Rerouted coolant hose from water pump to back of head. Plugged hose from water pump around back of block(heatercore hose) , and ran heater core hose out of head back to thermostat housing. Drilled and tapped. Now temps at back of head are 20 degrees cooler than front, so i will put a restrictor in hose coming from back of head, so thermostat can work, more like it should.Idea from LS1/x steam ports.