no spark injectors not fireing

[borsig]

car will not start speed and reference signal new and gapped correctly new dme relay checked grounds clean and tight fuel pump works and is new replaced the chips in the computers with the stock ones and the car still will not start thanks for any help

[TSNAPCRACKLEPOP]

hmmm, need more info.

did you have this engine apart to some extent?

check fuses and wiring and plugs to injectors. somewhere there is a test light procedure online, clarks or pelican.


did you have the injectors out for cleaning or rebuild? did you test them on the bench?

fuel pressure check? carefully loosen line while pal turns engine over, fire extinguisher ready.

need some feedback.

[TSNAPCRACKLEPOP]

spark at plug?

rotor in place?

[TSNAPCRACKLEPOP]

what year, model, engine, etc?

[borsig]

it is a 1986 944 turbo with stock 2.5 they are new injectors which came with a sheet showing me they tested them i have fuel pressure and i used a noid light to test for signal. the rotor is on and tight

[carsonmx114]

you probably don't want to hear this but i would start thinking about the dme unit. why did you replace the speed and reference sensors? how did the car get in the shape it's in now? not trying to be smart, but at what point did the car stop running in relation to when you replaced the parts that you've replaced?

[KY944S]

If it is equipped with an alarm check out the alarm box. Clark's Garage covers this. It can cause poor idle, hard or no starting. I had to bypass mine to get her up and running.

[borsig]

i upgraded the injectors and the sensors are new from when i rebuilt the motor which has little over 2,000 miles on it the car was running fine haven't had any problems. then one night i was driving and went to pass a car and it hesitated and didn't want to idle after that and i would have to restart it and it kept getting harder and harder to start and now it just wont start

[carsonmx114]

i know a guy with an auto 944n/a and his car did something like that but what happened was the damper on the flywheel came apart and damaged either the reference or the speed sensor. i think you need a osciliscope to check these but i wonder if you could plug in one of your old sensors and pass a screwdriver over it with the key on and a spark tester on the plugwire to see if it fires? maybe you could ohm out the sensors to see if they are damaged without removing them. my frien said he accidently pulled out in front of someone so he floored it and his car made a big thud and stalled, he pulled over and the car restarted and ran rough then stalled again and wouldn't restart. i know your car is not a auto but maybe your pickup stud backed out or a loose bolt or something took out the inside of one of the sensors.

[borsig]

thats what i was thinking may have happened so i pulled them out the other day both are clean and all the pins are in the flywheel

[carsonmx114]

do you have fire at the plugs?, at the coil? do the have 12v at the injectors? did you say your fuel pump is working? i wonder if your boost presure blew something off under the intake when you passed that car that has created a big vacuum leak, that would explain it running rough for awhile.

[borsig]

no spark at plugs or coil yes fuel pump is working not sure if the injectors are geting 12 volts just know that they are not firing

[carsonmx114]

check for battery voltage on pin 3 in the plug by the brake booster. also remove the dme and kcp units turn on the key, check for battery voltage between pin 35 and 5 and also 18 and 5 of the dme. check for voltage between pin6 and 14 of the kcp plug. my manual listed the tps as a possible no start problem, try unpluging the trottle position sensor and see if it makes a difference. i'm still leaning towards a bad control unit, but maybe you've got a broken wire somewhere.

[borsig]

i will try checking voltage tom when i go to work thanks for the help