wont start (not starter contacts) (1 Viewer)

[RavenTai]

Haven’t damaged anything yet it the interior comes apart fairly straight foreword

I latched on to the ground point because I chased a dropped screw under the console during the headliner install thought I might have damaged it blindly groping under there, after I found out that was where the pumps ground was it clicked in my mind but turned into a wild goose chase,

I wanted to pull the carpet and clean it anyway never had a good reason to do so, the PO's 2 kids were not easy on it,

Checking for voltage is going to be interesting because I already have voltage (with no load) at the fuel pump connector, the connectors in the cab should be "non waterproof" and I may be able to slide the test probe in from the wire side without disconnecting the connector to get a voltage reading with the pump load

First thing I did was a visual check of the fusible links and important fuses, including EFI and IGN now that it is narrowed down to one system will give them a more thorough examination to the related fuses, but I would think a fuse would fully opne, not give the symptoms I have,

Picked up an EFI relay at the dealer on the way to work, figured even if that’s not it, an EFI relay is a good thing to have as a spare of in the glove box, it looks just like the horn relay next to it but the part #’s were different so I did not try a swap, I would imagine that relay sees a more current and tougher duty cycle than the horn

Going to try get up early enough tomorrow to check it out further, need to get the cruiser running, gas for the truck is expensive (11-12MPG)

 

[ppc]

"Checked + wire to fuel pump (pin 3) key on 0v cranking get 10.2v sounds about right for battery voltage with the starter drawing from it,"

I don't completely understand the above statement with what you just posted:

"Checking for voltage is going to be interesting because I already have voltage (with no load) at the fuel pump "


With the key "on" you should have full battery voltage to the pump. The fuel pump relay is controlled by the ECU and should be at high voltage as it appears to be ("10v cranking").

 

[RavenTai]

"


With the key "on" you should have full battery voltage to the pump. The fuel pump relay is controlled by the ECU and should be at high voltage as it appears to be ("10v cranking").

According to what Gumby posted the ECM will only turn on the pump if it see's either cranking of the starter or a running engine through the crankshaft position sensor, is that not correct?

 

[RavenTai]

was not the EFI relay,

for some reason I thought I read 3-6 ohms, just reread it it is 2-3, mine is 6 hmmm, gonna pierce it and see what the loaded voltage is


8. INSPECT FUEL PUMP RESISTANCE
Using an ohmmeter, measure the resistance between the terminals
3 and 6.
Resistance: 0.2 – 3.0 at 20°C (68°F)
If the resistance is not as specified, replace the fuel pump.

 

[RavenTai]

OK pierced the wire with a pin, going to seal it with rtv later, have almost no voltage to the pump cranking with the pump load connected, with it disconnected I still get 10+ volts, pump resistance is .5-.6 not 6.0 like I read earlier, read error :whoops:

 

[RavenTai]

reseated the Fuel pump relay and it started

Thanks for the help,

 

[ppc]

It may be a bad wire in the harness as well. It might pay to wiggle some wires in the same area and make sure every thing still is OK. Better to have the problem reoccur now instead of when the wife is alone late at night in a parking lot at the mall.

Just to clarify from above if you hot wired the fuel pump and it worked you should have been able to eliminate that as the problem. Did you take voltage measurements at the relays and other connectors? Logically work from one direction to the other. A relatively small increase in resistance may cause the pump to be weaker than new, but it would not totally stop pumping.

Rather than sticking pins through wires I would invest in, or construct some jumper wires with alligator clips, various types and sizes of spade lugs etc. for testing. Pull the connectors apart and jumper as required to insert the test meter inline. This will yield much more consistent results and nondestructive to the wiring.

 

[RavenTai]

It may be a bad wire in the harness as well. It might pay to wiggle some wires in the same area and make sure every thing still is OK. Better to have the problem reoccur now instead of when the wife is alone late at night in a parking lot at the mall.

agreed I need to look into it more, but ran out of time had to leave for work, just glad to have it running again, have an possible idea of why, not sure, more on that later, going to Alaska this weekend for the Sockeye season so may be a wile

Just to clarify from above if you hot wired the fuel pump and it worked you should have been able to eliminate that as the problem. Did you take voltage measurements at the relays and other connectors? Logically work from one direction to the other.

Would have had the same problem when any part is disconnected without a load I had battery voltage all the way to the pump and have a hard time getting to the wires or terminals on the waterproof connectors when assembled

A relatively small increase in resistance may cause the pump to be weaker than new, but it would not totally stop pumping.

Rather than sticking pins through wires I would invest in, or construct some jumper wires with alligator clips, various types and sizes of spade lugs etc. for testing. Pull the connectors apart and jumper as required to insert the test meter inline. This will yield much more consistent results and nondestructive to the wiring.

yes I need some of the narrow Toyota style terminals to do interesting things like that, do not have any and never going to find any in Newnan GA, alligator clips would work on the male side but not the female, got a neat jumper to work with when I installed the CDL switch, just that one piece has already been very handy. Can we get bare terminals from the dealer? Can you use standard crimpers? if not wonder if Ideal makes a jaw set for my ratcheting crimper, if I could find some raw stock that was the size of the terminals could turn a female into male and use clips for troubleshooting, but having the terminals and crimper would be more handy to repair harnesses if needed

 

[RavenTai]

wonder if Ideal makes a jaw set for my ratcheting crimper,

yep they have them now just need the terminals

Item ID: 30-586
http://www.idealindustries.com

 

[cruiserdan]

Toyota does not offer loose terminals, They Do offer repair splices that consist of a terminal with an attached length of wire (about 6 inches)

 

[RavenTai]

Toyota does not offer loose terminals, They Do offer repair splices that consist of a terminal with an attached length of wire (about 6 inches)

Bummer, I guess those would work for this purpose,

Update:

After reseating the fuel pump relay the problem moved from hard fault to intermittent, some times it would not start tapping the relay would get it going, after it starts it runs fine until I step deep into the skinny pedal where sometimes it looses all power, returning to idle and it runs again, that is consistent with the high voltage setting of the relay (starting and high poser settings = battV all other times around 8V )

Stopped in the local dealer on the way to work expecting to pay 20 or 30 $ and they wanted $98 for a relay! and did not have it in stock, not available at any of the part stores so I took it apart and cleaned the contacts, they were not pitted or sooty looking or any other visual problems with the contacts

When I first got the cruiser I started putting dielectric grease on any connector I disassemble, this was one of the first I removed, I think to get it out of the way to access to the inner fender, the grease I got at the parts store is not doing well after only a few months it is separating into two parts an oil and a thick opaque white gel, there was some of this or a similar looking oil in the bottom of the relay did not see any on or around the contacts so may be coincidental?

So far the problem has not returned

Picked up some Dow Corning DC-4 in the next town over, it was expensive but better that having problems, the parts store stuff is going in the trash going to keep the dielectric grease away from relays from now on just in case

 

[IdahoDoug]

So, do you think the d-grease is separating into an conductive component and a non conductive component? Seems like the non-c component was dropping the voltage in the relay enough that it would not provide high power operation consistently. What's your take on it?

I'm asking because I also started using dielectric grease from the parts store a year ago and should know what's taking place with yours for my future reference.

DougM

 

[Rich]

There are no conductive components in dielectric grease. It's is supposed to be entirelyl nonconductive. The purpose is to prevent moisture and other corrosive materials from contacting the terminals.

 

[RavenTai]

pure speculation:

it may be possible that some of this oil got in between the contacts, unlike a connector that will push the insulating grease out to get metal to metal conductive contact a relay is light pressure it may not have had enough pressure to squeeze out the oil stuff, but the contact is donsiderably elevated in the realy housing and there was just a slight seep stain of this oil in the bottom so the problem might have been something else?

 

[RavenTai]

Update:

My original cleaned Fuel Pump Relay started giving me trouble again earlier today, was running a lot of errands all day, tapping the relay got it going, after about 10 starts gave up and switched it out for the spare used relay I had waiting in the glove box for this eventuality.

Started right up.

I’ll actually bolt it up in the morning, instead of just plugged in and sitting on the fender.

Guess I will have to pony up $100 for a new relay to be the new spare in the glove box, do not feel safe without a replacemnt waiting in the wing.

 

[Mickldo]

You were talking earlier about piercing the wire to check the voltages. When I do electrical diagnosis work I use a paper clip straightened out to back probe the connector. You can still usually access the metal of the connector pin even with "waterproof" connectors. This prevents having to pierce the wiring causing a potential spot for corrosion. Don't know if this technique is possible on these particular connectors as I don't have a petrol cruiser to check but this normally works a treat.

There was also a bit of discussion on contact points and dielectric grease. Personally I use the stuff everywhere but when I worked at a 4x4 hire place we used to have to replace ignition points all the time and we figured out that it was the WD40 that everybody sprayed into the dizzy cap to try and dry it out after a drowning. The points would be in perfect condition before a trip and be shot within a couple of days after being sprayed. We found it was heaps better to dry the inside of the dizzy with a rag or compressed air. Use WD40 on the rest of the system by all means but keep it away from the points unless you wanted to change them soon. Maybe the dielectric grease had a similar effect on the relays points.

 

[RavenTai]

the pierced wire got sealed up with RTV, you are correct though it is a hack. If I run into the need again I will give a paper clip a try that sounds like a good idea.

I do not know what effect if any the Dielectric greases had on the relay, since this thread have read of several other people having troubles with the fuel pump relay so it may just be coincidental.

But I still do not use it on relays connectores just in case, every other kind of connection gets DC4