have u recently done any kind of work to your car as far as engine mods(ignition mods)? possble maybe spark plug wires crossed, make sure they're 4-1-2-3. Unless u have link with a '95 eprom, and your CAS should be inverted in link too and your plug wires should be 3-2-1-4. You say u have spark? which way did youcheck for it? You could checkthe pin-out voltage off your ECU that goes to those injectors. Oh and by the way what kind of car is it?

it's a 1991 Plymouth Laser RS and I bought too plugs and wires to see if that was the problem and it didn't fix it. i'm positive the wires are on the right spot. to check for spark i pulled the plugs out of the head and turned over the engine and the spark jumped about an inch. i haven't done anything in ways of ignition mods either. i also checked all the injectors and they were 3 ohms each. which part of my ecu do i need to check?

Please don't take any offense, but how do you know specifically that 3 and 4 fired and not 1 and 2?

double check the spark plug wires cause it seems like they are crossed or possibly the compression on the number 1 and 2 are to low to even run

i can let me car run for a few minutes and touch my exhaust manifold on cylinders 1 and 2 (which are closest to the driver side) and it's not even warm. when i can't even try to touch cylinders 3 and 4 on my manifold. and i checked compression and they were all the same. not to mention they're not going to go out at the same time are they?

bad coil pack possibly? somehow..

but i have what appears to me the same amount of spark on each spark plug

odormat000 said:

i can let me car run for a few minutes and touch my exhaust manifold on cylinders 1 and 2 (which are closest to the driver side) and it's not even warm. when i can't even try to touch cylinders 3 and 4 on my manifold. and i checked compression and they were all the same. not to mention they're not going to go out at the same time are they?

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if the gasket between the cylinders blew they would

thewombis said:

bad coil pack possibly? somehow..

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if 4 and 3 are firing then so should 1 and 2 due to 4 and 1 being the same coil pack and 2 and 3 being the same

banishedmunk said:

if 4 and 3 are firing then so should 1 and 2 due to 4 and 1 being the same coil pack and 2 and 3 being the same

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yeah that's what i was thinking

i called a shop who does only dsm's and they said they had a guy bring a car in with the same problem and it turned out to be the CAS. Also he said maybe my ECU has a leaker in it causing stuff to go wrong. i'll have to check it out. It would be a good excuse to go EPROM haha

Sounds like a timing issue to me. I would check the CAS.

if the points inside the cas are bad and you decide to change it please ensure you have the motor at tdc prior to removal

can only two points be bad?

ecu?

Crank it over and pull the plugs out of the two dead cyls, see if there is any fuel actually getting to those cylinders.
Another way of doing it would be by putting a noid light on those injector connector and see if they flash.

my friends 2g transistor was bad and caused to too fire and two that didnt fire

yes it is possible for only two points to be bad

pj91gsx said:

my friends 2g transistor was bad and caused to too fire and two that didnt fire

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Yes its possible, but the OP says he has spark on all 4. Also if it failed it would be 1,4 or 2,3 paired that would not be firing rather than 3,4 not firing.

aero_sallee said:

Yes its possible, but the OP says he has spark on all 4. Also if it failed it would be 1,4 or 2,3 paired that would not be firing rather than 3,4 not firing.

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my friends didnt fire 2 and 3. then we changed the transistor and it worked

the reason being is that 2 and three are both on the same coil the problem lies some where else he is not getting fire from 1 and two both of which are on separate coils

ok people so i am at a true stump on fixing my car. i have done almost every test there is and still can't figure out what's wrong with my car. cylinders 1 and 2 won't fire. all cylinders have good compression. plugs have spark. pulled off CAS and then spun it and all injectors fired. all injectors have 3 ohms. pulled out my ecu to check for a leaker and it looks perfect. Does anyone know of a way to test my ECU when it's out of my car to make sure it's not one of the problems? does anyone know of any other tests i should do to see how to fix this piece of crap on the side of my house? PLEASE HELP ME!!!!

Seriously, I would do what others have said in this thread....check that power transistor. I had the same thing happen in the Laser.

so i replaced my CAS and it didn't change a thing. how do i check the power transistor?

http://www.dsmtuners.com/forums/articles-electrical-wiring/229419-how-test-power-transistors.html nvm i found it.

can someone tell me if this could actually be the problem though? considering that when you do a test it tests cylinders 1,4 and 2,3

how will this test help?