1989 buick century 3.3 V6 has no spark. Changed ign module, coils, crank senor, maf sensor, computer, ign switch. Traced wires no breaks fuses and fusible links are good. What can i do next?

I0check your ignition fuse, and check the ign. coil for spark. Pull the coil wire off and see if you have spark from the coil.

What fault codes do you have?

Check compression. I have a feeling you have a broken cam shaft which is pretty common for these vehicles.

also you never mentioned if you actually checked for spark at the spark plugs. If the plugs are wet with fuel than the Crank sensors are working since the computer needs that signal to determine injector pulse and spark.

If there is no spark out of the coil pack or the wires at the plugs than there is a good chance the ignition module under the coils is bad.

good luck and keep me up to date with any findings or new info and ill do my best to guide you in the right direction.

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

I'm not sure of engine Size? Did you check the crank sensor? Any applicable trouble codes? Do you have a fuel injector pulse, engine cranking?

no spark to all 6 cylinders, or just 2 ????????????????????????
did you check all fuses first??????????
did you check that the CEL lamp glows, key on? MIL lamp?
if not? the main is dead, or fuse dead.(blown)
ok this is the very very old and obscure Jeep Bendix/Renix system.
the hard part is , it is NOT OBD1 engine yet, making diagnosis very hard. and no distributor. (new for MPI)


is yours the 4.0 I-6
and is it the 1 year, MPI engine? WITH MAF SENSOR!!
this is and AIR DENSITY SYSTEM unlike most other jeeps.
1989 - Changed to Renix MPFI. (read 4 injectors now>....)
i owned a 88 Comanche, love it. 200,k miles i drove from 0
other that ISC motor, zero issues. mine was TBI , no MAF.
NO spark.,?
this MPI has a coil pack with 3 coils in side, and uses the famous.
wasted spark design, even my new jeep v6 has this.
the coil is driven by a separate ICM , ignition control module.
The ICM, iis driven by the PCM(ECU)

your car has a CKP sensor (crank) fitted to the BELL
for the 3 marks, on the flywheel
quote FSM.
The Crankshaft Position Sensor (CKP) is secured by special shouldered bolts to the flywheel/drive plate housing. It is preset in its mounting at the factory and is non-adjustable in the field.
uq:
this means it tunes like a marconi radio, its not a hall sensor...!!!
its just a coil with weak outputs.
is it loose?
id do not know where the CAm CMP sensor is.
the online books mix 5 systems bad, this engine was EFI was
a one year only system. (French)
My wild guess is the CMP is this funny device, on the right
side of engine, where the DIZZY USED to be. called the cam sensor.
that too, must work and i think its a hall sensor and is very easy to test.
sadly no OBD1 and no CEL: flash codes.
to blink out, CMP/CKP dead. cranking
just very old factory scan tool works

again, all spark dead or only 2?

Can position sensor, maybe, or it might be called a pick-up coil. This sensor is needed along with crank position sensor for computer to determine spark timing.
When you get it started, and if you still have the up and down idle, check for an intake manifold leak.

Check all your fuses, under the hood and at the fuse panel for ign fuse or ecm fuse and make sure they are'nt blown, then check for power to ign module which is under the coil paks, should be pink wire. good luck...sounds like maybe your ign module or crank sensor may have gone bad.

1. Monitor the 5v reference, Gray wire to the Throttle Position Sensor (TPS) with a Digital Volt Ohm Meter (DVOM) set to the MIN/MAX setting.

2. Monitor the TPS signal circuit, Blue wire with a DVOM. Voltage should range smoothly from approximately 0.44 to 5.0 volts as the throttle is opened.

3. Tap test the Electronic Control Module (ECM) and see if the codes come back or if the engine reacts.

possible causes wiring or Powertrain Control Module (PCM)

Did you replace the crank sensor that is bolted to the back of the module? Is it possible that you got two of the plug wires switched. Or maybe 1 of the two coils is bad.

the 3 coils are mounted to the ignition module and as long as the sensors that signal the module to fire the coils individually are working I would try a module especially if all 3 coils are not firing..also if you have an ohmmeter for checking electrical resistance, the spec for the coils are 5000 to7000 ohms, measured between each coil from tower to tower (ie) #1and#4 2+5 and 3+6 any more than that and the coils are toasted..lol hope this helps also check the spark plug wires at each end maximum resistance is no more than 1000 ohms per inch,,,good luck