1992 4 cyl dakota running very lean
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1992 4 cyl dakota running very lean
We recently rebuilt the 4 cyl engine in one of our four 1st gen dakotas, a 1992. We actually used the block and head from our '87 (2.2 L) but put all of the accessories (FI, alt, distributor, etc) from the 92. The engine idles fine but appears to starve for fuel once it is hot. The power actually goes DOWN as you put the accelerator all the way to the floor in 4th or 5th gear. The computer isn't generating any codes that we can see (key on-off-on, counting the flashing lites, etc). We have two temp guages on the motor, the original on the panel which measures the cyl head temp and an "old school" mechanical / bulb aftermarket guage. It goes almost into the red under heavy load every time. The aftermarket guage measures the water temp at the thermostat housing and stays rock steady at 190 degrees! Wierd unless the motor is running so lean that the cylinder head is overheating and there isn't enough cooling flow to keep up with it.
The original fuel filter had a lot of really small black particles in it (replaced) and we cleaned out the regulator and injector as best we could. Our thinking at this time is either there is another partial blockage somewhere in the fuel system or the computer is telling it to run way to lean at low manifold pressure/open throttle valve for reasons unknown. Fuel pressure at the trottle body is 17PSI. Any thoughts will be greatly appreciated. Truck came from Charleston, SC (near ocean, etc) and has a 5 speed manual with AC.
We have checked the cam belt timing a couple of times and it appears to be "right". Timing is at 12 degrees BTC with temp probe disconnected. Don't want to just throw money at the problem replacing the injector, EGR, O2 sensor, etc. if somebody can help figure this out.
We are new to Dodge FI and any help will be greatly appreciated
The original fuel filter had a lot of really small black particles in it (replaced) and we cleaned out the regulator and injector as best we could. Our thinking at this time is either there is another partial blockage somewhere in the fuel system or the computer is telling it to run way to lean at low manifold pressure/open throttle valve for reasons unknown. Fuel pressure at the trottle body is 17PSI. Any thoughts will be greatly appreciated. Truck came from Charleston, SC (near ocean, etc) and has a 5 speed manual with AC.
We have checked the cam belt timing a couple of times and it appears to be "right". Timing is at 12 degrees BTC with temp probe disconnected. Don't want to just throw money at the problem replacing the injector, EGR, O2 sensor, etc. if somebody can help figure this out.
We are new to Dodge FI and any help will be greatly appreciated
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From: NM
You said your fuel pressure is a 17psi. Do you know what the specs for your year is? For magnum 92-up it is something like 35psi. So if yours is somewhere up there your pressure is low. Change a fuel pressure regulator or a fuel pump may be your fix.
The O2 sensor or EGR could be your problem as well. I'm not 100% but I believe your O2 would be the cheep 1 wire kind. You can go to www.autozone.com and check.
The O2 sensor or EGR could be your problem as well. I'm not 100% but I believe your O2 would be the cheep 1 wire kind. You can go to www.autozone.com and check.
