Minor Car starting issues

[Z Tyler Z]

Well once again my car is giving me trouble; this time in the starting department.

Long story short I decided to drive my car over to my cousin's house because the weather was decent and I needed to catch up with him a bit. My car drives perfect all the way over there. Then about 10 after I get there I need to move my car to let someone out who i blocked in and my car won't start.

The engine was turning over but not firing up. I pop the hood and look for loose connections and check the fuses (Dave and I replaced the fusible links with a maxifuse block thing) but still the car only wouldn't fire up.

We ended up pushing my car out of the way so the person I was blocking in could leave. After I went to start the car and it fired right up. Maybe 10 minutes passed during all of this.

A few days previously I drove the car to work because Dave and I were going to replace the brake booster afterwords and I had a similar problem. I went to first start the car and nothing happened besides the engine turning over. After cranking for a 20-30 seconds it finally slowly started, had to give it a little gas to keep it afloat for the first few seconds but afterwords it drove great the rest of the day. Even after it sat for four hours while I was at work.

I searched around a bit on this forum and think it could maybe be a check valve problem or water temp sensor problem?

Instead of starting new threads here's a few other minor questions.

Unrelated to this I sometimes see a little white smoke when I start the car after letting it sit for a few days. When I start to drive it goes away immediately. My oil is fine I just assume it's condensation in the exhaust causes this but need a little reassurance.

Also unrelated has anybody installed Toyota 4X4 4 piston brake upgrade using 14X5.5 rims? I've searched both here and HybridZ and can't find any specific answer. I'm just talking about the smallest 4 piston upgrade the non vented one.

As always thanks for everyone's help thus far with my Z. Without this forum (and Dave) I'd be way over my head with this project.

[Zs-ondabrain]

Any one??? I (we) could use a little more help on this. I don't typically do Fuel injected motors so I'm standing here scratching my head on this one.

Please help us figure this out.

Dave

[AnthonyG]

working from the back to front - Is the fuel tank ok? are there particulates in the tank that could sometimes block the intake? is the fuel pump making noise? is it delivering fuel? is the fuel filter starting to clog?

are the injectors getting their signals to fire? is there spark?

I had an intermittent issue that i had to wait for it to recur and finally tracked it down to a bad fuel injector electrical connection.

if it is a sensor, check measurements from manual, but some sensors can fail intermittently too. given the cost of the sensors, may want to replace them just to eliminate them as a possibility.

Divide and conquer troubleshooting worked well for me on my fuel injection system. divide into fuel delivery, electrical - power, and electrical- computer (sensors, etc). and always subdivide based on cost - replace cheap parts first.

(there will be others that know more about this system. so hopefully they will chime in soon)

[Pomorza]

The white smoke could be condensation that was in the exhaust. I've personally had this happen to me and I'm positive its not coolant. But just in case keep a nice keen eye on the fluid level. As for the starting problem. Did your fuel pump turn on and pump fuel? Did you guys inspect the TPS or the CSV? I'm thinking there are two possibilities. One, your engine is getting flooded with fuel when you try to restart. It is possible that you have a broken CSV (cold start valve) or one(or more) of your injectors is not sealed properly and is leaking. Second, your car is leaned out too much to start. I have the same problem with my Z at the moment. It is possible your water temp sensor is bad. Testing them is fairly easy if you have a FSM. If your don't download one and get with the trouble shooting.

That's an idea

Jan

[grantf]

I have a 78 280z and have the white smoke the same as you, after it sits awhile. I don't really know what it is but it goes away so I am not to concerned. I think this sounds like fuel delivery. check the fuel pump as rust can hamper if not ruin it, also the fuel filter. If you do suspect rust is an issue you should install a cheap filter inline right after the fuel tank. hope this helps.

[ZCurves]

Everyone has good advice here...FWIW, I think that you should carry a ignition tester with you in the car (something simple to see if you are getting a spark). When the problem reoccurs, check for spark. I am thinking that there is a intermittent Ignition Module issue. Check the connections and wiring harness to the distributor. I believe that a member (OldHemi) had a similar issue. You should PM him.

As for the White Smoke, it is actually Steam created from condensation in the exhaust. It is completely normal and should go away after the car has run a while. What is not normal is little whiffs of steam after the car has warmed up -especially in the summertime, that could be a failed Head Gasket or cracked head.

[FastWoman]

What everyone else has said. In addition...

It's not the fuel pump check valve. A failed CV can result in hard starting when the car sits any time, but the engine should still fire up with a bit of cranking. Furthermore, the car won't magically start after 20 or 30 min after refusing to start previously. The fuel pump still has to clear out the air in the lines.