iaphatcook

Have a 98 pickup w/ 4.3 V-6that has issues with electrical or fuel system. Engines cranks well, but seems to be no spark or fuel starved. Replaced fuel filter and seemed to want to start and when pressing pedal to the floor could get wiff of fuel smell. It's cold here in Iowa, so really don't want to spend much time outside doing troubleshooting work. Any help would be greatly appreciated!

dewey

If it cranks good but won't start, have a helper crank it, while you check for spark at the plugs. You can pull a plug boot, stick a know good plug in the boot, lay metal part of plug against metal part of engine, have helper crank it while you watch for spark at the tip of the plug. You could also get a cheap spark tester from the autostore.

RonH

Back in the old days, you tested for spark by getting the "new guy" to stick a screwdriver into the plug boot and then hold onto the screwdriver blade with one hand and put his other hand on the fender while you cranked it over. That was before cell phones and quartz watches and other electronic stuff. Best to leave those items somewhere else when you are using this method.

dewey

I hear you, the last time I checked for spark using a screwdriver in the plug boot, was on dis ignition. I didn't see the spark, but I darn sure felt it. I was holding the insulated handle with the blade close to engine ground. It just about ate me alive. I don't know if the handle had a crack or was greasy or what. I guess the easiest path to ground was through me. I was dancing a gig, hollering at the helper to turn the key off. Everybody had a good laugh, I wasn't laughing.

I just wanted to add, when I was a kid, I remember watching my neighbor check for spark on his old car. He used two ice-picks, the tip of one ice-pick, he touched to the engine block, the other, he stuck in the plug-wire. Held the shanks of the two ice-picks close together, had a helper crank the engine, while he watched for spark to jump from one ice-pick to the other. He was holding the wooden handles.

I wouldn't do that on todays ignition systems, even if the voltage didn't bother you, it's probably not a good idea to punch holes in the plug-wire.

iaphatcook

We put the fuel pressure gauge on it, 59-60psi with key on engine off. Checked the spark and besides needing some new plugs and wires, it has good spark. Couple of the plugs are really bad, but still having a hard time thinking it won't at least run or try to run in this state. Going to change plugs and wires and see what happens. Any other ideas?

dewey

Are there any codes? Can you put a scanner on it? Can you look at fuel trims?

You might take the air-duct loose from the throttle-body, spray a little carb cleaner into the throttle-body. Try not to spray it on any sensors. If it starts or tries to start, I think it is a fuel issue. Any time you use a flammable spray you need to be cautious.

If you have fuel-- air-- spark, I can't think of much else. Compression--- timing--- exhaust restriction?

I just wanted to add, It could be a sensor issue. If you can't do any sensor testing, you might unplug the sensors one at a time, then see if it starts. If the sensor is providing a faulty signal and you unplug it, the computer may use a default value. Don't unplug or plug anything without turning the key off. Unplugging sensors just to see what happens may be poor diagnostics, but without being able to check for codes or look at live vehicle data, even koeo. I'm not sure where to go next.

iaphatcook

Put some new plugs and ohmed the wires and still cranks but no start. When the key is turned on the fuel pump runs and when I turn the key off the pump runs and from right side of intake manifold I here a hissing sound. I have a haynes manual, but pictures aren't to good of the fuel injection system. Anyone have a better pic of the Inj. sys for CSFI ingnition? Thanks in advance.