96 T100 with 3.4, auto, 230,000 miles, ran great for 2 years with out a hitch. Now it will crank, but only run for 2-3 seconds then quit. I have changed the Fuel Pump, Fuel filter, Crank sensor and cam sensor still the same. Cleaned the MAF also. Put some ether in it and it ran as long as you sprayed it. Cannot find any breaks in the wires, fuses good, throttle sensor works, no broken vacum lines. Seems as though cyl 1 and 4 dont fire. Changed the coils around and it is the same. need next step

You checked all the ground wires on the engine?
Check the COR....circuit opening relay. There are threads around here how to test it.

No CEL before this started happening?
Vehicle exposed to any water flooding?

Double ckecking the grounds again. Will try the cor test and hot jumping the fuel pump

What do the codes say?

:wabbit2:

No scanner and all local shops full till after hlodays. Will the scanner from autozone work it is $179 ?

Any local auto parts will scan it and pull codes for free.

:wabbit2:

Local is 10 miles others is 30 miles. Truck wont run and dont have a trailer

Have the codes 1. P0100...Mass Airflow (MAF) sensor error circuit 2. P0110...Intake Air Temperature (IAT) sensor circuit 3.P1300 or P0300 Random Cylinder misfire detected

By reading the book (Haynes repair Manual) 1 & 2 work together ( i think) and 3 probably occurred when we were testing the coils for spark.

Next questions-- what models use the same MAF sensor as i will be going to the parts yard tomorrow. Where is the IAT as the book doesnt show it.
any additional guidance will greatly be received

Still dead in the water. Bought a new maf no change so i took it to a mechanic and he said it looks like the ignitor. Bought a new one and still the same. He said he has no other ideas so the truck is back in my shop. Any more suggestions. How about the ecm?
Would i have this problem if the tps was bad?

The IAT is built into the MAF. ECM is the last on the diagnostic check list.

Have you taken a look at the ECM connections to be sure they are tight?
ECM is dry....no leaks soaking it?
All ground wires under the hood tight and making contact to bare metal (near battery, driver side intake, and rear of engine on passenger side?
Any chafed wires or where a mouse has stripped it bare?
All vacuum lines in their proper place?
Air filter clean?

Have you pulled the front cover and looked at the timing belt?
The crank pulley is properly torqued down?

Any other electrical components like lights, radio, blinkers, fan, etc. not working since engine incident?

Look at a FSM (see my sig)....the diagnostics are good.

Will follow your suggestions in the morning

Ok back again. Checked all that has been suggested and all seems correect ref fsm. Question on injectors, since the engine will run on ether could an injector(s) be clogged and the ecm ( just like new visually) be putting it in fail safe mode (the fuel filter was bad, black chunks coming out)? 2. Found a company in miaml that can build an ecm for $250 is it too good to be true. Good thing im learning ever day. Thanks again for your help

clogged injectors will not trigger your code. I would check/replace the COR. If you can try to hotwire the fuel pump and see if it runs. The MAF sensor sends a signal to the COR to kick on the fuel pump.

93 camry has the same mas air sensor. it will work just fine.
and an iat? do you mean an iac (idle air control) valve. it bolts up under the throttle body.