Question Asked: Did compression test, and now it has a crank-no start condition. No spark.
January 04, 2015, 04:26 AM
Ok. I work for GM and do this stuff for a living. I have access to ALLDATA. The car came to me running. It needs work, and we wanted to know if the engine was any good before putting money into it. I did a basic compression test. All cylinders between 100-110. Put the plugs back in and wires back on. Now it cranks and won't start. Got fuel, but no spark from coil wire to dist cap. Fuses are good. Tested coil. Primary side failed at 58 ohms (spec is 0.3 - 0.4) Replaced coil. Same issue. Tested ICM. It failed. Replaced Ignition Control Module. Same issue. Swapped whole distributor (I had one off an old motor). Same problem. Put new ICM in the swapped distributor. Same problem. Verified wiring between ECM pin A20 to ICM (green/yellow wire). Verified B+ voltage between ECM pins B5 and A26 (and 7.5A Starter Signal Fuse) during cranking. With a (Snap On) scanner on it, I see RPM (Engine Speed) signal during cranking. Coil wire tests at 1040 Ohms. Started over. Retested coil- now tests good. Retested ICM - tests bad again. Now I'm stuck. I have now tried 3 different ICM(s) and it keeps testing bad. Either my DVOM or ALLDATA is wrong. Or I truly have 3 (including 1 new) bad ICM(s). Any ideas/tests/help would be appreciated.
Question Answered: What could be the reason my car is dragging after acceleration?
September 25, 2013, 06:59 AM
Need lots more info to help you. Does this only happen when the car is at normal operating temp? When you say "stopped", do you mean shut off and re-started or after the first time you come to a stop? Does it do it cold? Is it only after you have been on the freeway and then get back to in town driving? When it drags, do the engine RPM's increase and the car just not go, or does the engine feel like it has a lack of power and the RPM don't climb at all? Any warnings or indicators come on? Have you had it scanned for codes? Please help us help you.
Question Answered: Oil pressure gauge reads zero after 20 minutes
September 18, 2013, 01:32 AM
Is the engine making any ticking or tapping noises? If not, then it is your sensor or guage. Screw in a manual guage in place of the oil pressure switch and get a reading. If there si no noise, chances are it'll read normal. To test the guage you need a variable resistor box (guage tester). Easier to just replace the sending unit and see what happens first.
Question Answered: Why won't my 89 Chevy caprice start?
September 18, 2013, 01:29 AM
Agree with pushrod. Not CRANKING and not STARTING are 2 very different things given what you said about replacing the column.
Question Answered: Will the oil pressure switch cause the motor not to change from 8 to 4 cylinder
September 18, 2013, 01:27 AM
Yes. It can cause issues with the AFM system. AFM will be disabled if the system sees (or thinks it sees) low oil psi. Check the wires to the switch and make sure they are not broken or shorted anywhere. If they are not, then replace the Oil PSI switch. If there are still issues after this, then you will need a scan tool (not a code scanner) for diag.
Why after just replacing my TC would it jump time as soon as the gear changed?
September 18, 2013, 01:11 AM
Aside from the timing chain tensioner, are you sure that the balance shafts and chain were installed correctly and timed correctly? Did the camshaft or crankshaft position sensors(s) get broken by chance? Tear down and re-inspect and line everything back up again. Pray you didn't do internal damage if anything is off.
Question Answered: Check engine light with codes 171 & 172.Shop said manifold gasket?
September 18, 2013, 01:03 AM
P0171 is a lean code and P0172 is a rich code. It could be the MAF sensor, but it sounds like it is air leaks. Grab a can of carb cleaner and spray along the edges of the intake manifold. See if the idle fluxuates or stumbles. Also listen to the engine when the vehicle starts up cold and see if you hear any exhaust leaks. An exhaust leak before the O2 sensor will cause problems as well. Try switching sides with the O2 sensors before the cat convertors and see if code(s) P0174 or P0175 set. You may just have a bad O2 sensor. If the code changes whent he sensor is moved, replace the sensor.