94 B2300 No Start with 3 pcm replacements!
 

Hi, hope someone can help me out here, i have as stated a 94 mazda b2300 pickup standard addition manual trans with a 2.3l. a month or so ago, i was pulling from a red light and it stalled out.. after tow to a garage, they told me the pcm had failed, but they wanted a lot for the replacement. too much.. so i ordered on from a dealer on line.. it arrived, garage says its still bad.. so they send it to cordone.. its repaired and sent back.. they put it in and guess what, still no start.. they did a pretty good wiring check..i can tell by all the holes and tape repairing them... so in short , it shows power to the injectors, and there is a solid 5.x volts going to the pcm, but no matter what there is no spark, the crank sensor has been replaced, twice, a new timing belt, kinda needed one. a new battery and a new icm as well, plus a new starter, burned up the one trying to start the vehicle.. so any way, per the mechanic, all flow test have led back to the pcm, not likely since three have been in there.. so ok any questions i will try to answer, but its been at the garage now for a month and it just sits cause they dont have a clue, im not in disperate need of the truck but i sure could use it.. HELP!!! someone has to know what the heck is going on...diode maybe?? :confused:

Do you hear the fuel pump engaging?

Have they tested for fuel pressure?

Willy: this truck is the same as a Ford Ranger 2.3. I suggest you post your question concurrently on the Ford Forum: Ford Forum - Enthusiast Forums for Ford Owners
Also go to the The Ranger Station - Your Ultimate Ranger Resource. They are dedicated to these trucks.

I am afraid it is not the PCM. Make sure you have good ground connections for all ignition parts. Take the coils off and clean the mounting points. Make sure you have a good ground connection from the engine block to the battery.

I don't know what the "icm" is.

yes they have.. and i can hear the pump myself kick in.

Ignition Control Module..

Thanks posting there as well..

Thanks.
I gather your model has the DIS (Distributor-less Ignition System) That could be helpful as you research the "rangerstation".
Another thing: I have changed the timing belt on a '97 B2300. When changing the timing belt one has to be very careful about the timing marks. There are 2 sprockets of the very same kind. One for the camshaft and one for the oil pump. Because of their different locations they put 2 timing marks on these sprockets. The triangle is for the camshaft location and the diamond is for the oil pump location. If any one of these, or even both of them are not matched correctly (triangle to triangle, diamond to diamond) then the engine won't start. You need to be aware that the camshaft position sensor is mounted at the the oil pump sprocket location.

I assume (but I am not 100% sure) that this also applies to your '94 model.
And don't overlook the ground connections. They are critical.

This was my first thought. ;) You never know, especially when dealing with older vehicles. I always put extra ground wires from the negative terminal of the battery to the: engine block, body, throttle body and transmission.

well its been a bit , i got the pos back today, it actually drove home,, the ground is likely were were at, but this is what they did, (after i spoke again to them ) the pcm component itself the case says its grounded, told me it wasn't supposed to be. but they found a wire that goes to the pcm, that is supposed to be grounded, it read that it was, red with a orange stripe.. they cut and grounded that and guess what,, now it runs.. anyway.. it called a code straight away,, block down the road.. i turned it off and on and it started right up.. i noticed at at that point that the tac wasn't working.. wel it sorta worked, it would get to 1000 rpm,, and just hang there,, unless i stopped at a red light.. then it would slow down like it should.. when i finally got home i wondered about the tak deal and got under the hood,, (i know they didn't fix it.. ) so i have to try it by myself and perhaps a bit of help from you guys..i found that if the code hits then it stalls, and when i restart it , it stalls, (tac working) then if i restart it the tac does the same as before, don't work quite right but it runs ok, sorta.. i can drive it.. but i want to fix it right.. just have no idea were to start...the only code it shows is tps, voltage out of range..

There you have something: Throttle position sensor. Richpin on Youtube has a nice video on how to check the TPS. So it is on a Saturn but it's still the same.

You say the tach is slowing down. I take this as the engine keeps revving just fine but the tachometer hand is dropping lower.

I recently, like 2 weeks ago, had to work on my Windstar's instrument panel. there is a printed circuit board and a board with the stepper motors for the speedo and the tach. there are plenty opportunities for corrosion to mess up the current. And when you take it apart there are opportunities to mess up the instrument hands and so on.
I never found the culprit but i did get it to work flawlessly again by carefully puting it back together.

I am not so sure about the shop you are using. Electronics doesn't appear to be their strength.

Dual Plug (DPI), SPOUT or IDM circuit fault -

any idea what its trying to tell me with this? No i brought it home because i also feel they dont know squat about electrical.. im sure there is a bad ground somewere. adn they couldnt find it. thye did figure out what wire to ground tho.. this is a orange wire with a red stripe.