Ignition System: Cranking very well but won't start 75 1.8FI, Fixed: Major concern Ignitor and #3 fuel injector. :THANKS TIM! Options

[ndfrigi]

Need help diagnose from members!

Well, last saturday Feb. 13 I joined fellow members at the Aliso Viejo Cars and Coffee which is about 30 miles one way. After the event, drove home and for less than 2.5 miles away from home at a traffic light, my tachometer is bouncing between 2.5k to 3k rpm (sorry not 3.5k to 4k rpm on what I have said on the other thread). But the actual is pretty much on normal idle of less than 1k rpm. When about to go on green light, engine died. Tried to start the engine but it is just cranking (cranking very well), but the engine won't engage.

Some good members here already mentioned about ignition circuit. Well today, I was able to checked and opened the rotor cap, and I found out that I have/had Pertronix Electronic Ignitor which I already forgot since the last time I opened it last 2011 (Since the engine is running very well after I was able to make it run after fixing it from the time I bought. I haven't open it since then. I even bought lately a spare of contact points and condenser to replace it soon).

So a friend of mine was here this morning and asked him to start the engine and try touching at the base cover of my front mounted fuel pump and I don't feel any vibration. So we tried to unplug fuel hose from the SS engine tunnel lines which is a direct supply line from fuel pump to engine bay before the fuel injector line. We did crank the engine but no fuel is spitting out from the line.

So is it fuel pump issue I have?

In addition, a member also mentioned about the fuel pump relay from the relay board. But after opening my relay board cover. I noticed there is some wiring that was changed/modified. No round relay for the fuel pump terminal.





Thanks again for your help!

[timothy_nd28]

Good, so you narrowed it down to no spark. Even if you did yank the FI stuff and installed carbs, the car will still not start.
Now we can narrow down to what's going on here. Let's retest that you are getting voltage to the ignition coil. Put a meter lead on the + side of the ignition coil and put the other meter lead to the negative battery post. Set your meter to DC volts, turn the ignition key to on, and observe that you are indeed reading 12 volts.

If you have 12vdc for that test, try this: Set your meter to ohms (resistance) and put one meter lead on the negative battery post. Remove and temporarily tape off the wire on the positive lug of the ignition coil. Take your other meter lead and connect it to the negative side of the ignition coil. Try starting the car, you should see the meter go from 0 ohms to infinite ohms. These readings should alternate rather fast, and your meter may not be able to keep up. If this is the case, you could swap out your digital multimeter with a old school analog meter. The analog meter will show the sweeps from infinity to 0 ohms. Or, you can simply put the car in 5th gear and slightly push the car while observing the meter. If you push the car slow enough, you will see the meter alternating from 0 to infinity ohms.