Leslie 928 S2

Its very possible that it is bad again. Do a search for the ohm test and test it instead of just replacing it. We have had some non bosch senders that were bad out of the box. We took a multimeter with us to the parts store and tested them right on the counter in front of the clerks.

We've found it's best to order them from a vendor here. As for replacing it two years ago, we keep spare in the glove box at all times. Good luck.

Leslie 928 S2

For argument's sake Kevin went outside and removed the plug from my cars temp II sender to simulate having a bad temp II sender that is not sending any signal to the computers. Guess what -- it attempts to start, floods and will not restart. Let it sit a few hours, the fuel dissipates and it attempts to start and floods again. Plug the temp II back in, car starts instantly. Do the ohm test, before just throwing any money at it, of course.

John Speake

Also check the plug from the harness that plugs into temp 2. Sometimes heat shrink sleeve from the wires melts down into the sockets in the harness plug.

How long the car will run with temp 2 open circuit depends very much on ambient temp. If it is really cold, it will run for a minute or so before choking up.

As a final check you could measure the temp 2 resistance at the disconnected LH 35way plug. Pins 13 and 17. You should get readings in the range 1500 ohms to 3500 ohms, depending on ambient temp and the tolerance on your temp2.

A very high reading - say > 10,000 ohms (10kohm) means that it the fault.

hinchcliffe

What is the voltage across the battery terminals? Pull a spark plug or two and see if they are wet.

I'm currently having a similar problem, ran fine a couple weeks agao, and I went to put her in storage for the year and no start. Wet plugs, but I haven't checked spark yet. I have 12.5 votls at the battery, so for me I'm going to try to charge up the battery and see if she'll turn over. If not I'll check spark and then be right in your boat. If she sarts You can borrow my LH if it'll work. Course I think the LH is different for '87 compared to '89, right?

oz928s4

An alternative fuel source will tell you whether or not it is electrical
Ezy start thru the intake while cranking...if it runs its electrical.
Quick way to to firstly 1/2 your odds

Leslie 928 S2

So JD, how did things work out for you?

JD928_S4

Well I did the ohm test this morning and found that there is infinite resistance from the LH pin on the Temp II and the body or ground of the temp II. Also the other day I bought a NOID light set and a spark plug test light. Basically bulbs that show when the injectors fire and the spark plug fires. I hooked it up and all is well. So there is spark and the injectors are opening. So the culprit seems to be the Temp II. Ill get a new one and go from there thanks for the help up till now and Ill keep everyone posted.

Regards,
Jacob

JD928_S4

ok Im an idiot I checked the the other temp sensor on the water bridge... Ill have to wait till I get home later to check the temp II... DOH

docmirror

If your wife or you have a hair dryer that is the best test. Get on the pins of the Temp II and check the resistance. Then, while on the pins have a helper shoot the hair dryer on high at the Temp II sensor. The reading should change quite a bit quickly.

If you find that your temp II sensor is working right, simply remove the MAF or at least the connector to the MAF and try to start the car. If it catches, press on the gas pedal immediately to get some fuel into the injectors. Don't press the pedal until after the engine catches. If you can keep it running with the gas pedal, then you likely have a bad MAF. If it still dies, prolly the LH.

Spritzing carb cleaner(not Ether) into the intake as you crank the engine is also a good test, but many on this board discount the method. If you can keep it running on carb cleaner, it's either MAF or LH.

A cheap but very useful tool for 928s is this digital Oscilloscope that runs off the USB of a computer:

http://cgi.ebay.com/PC-USB-Oscillosc...1%7C240%3A1318

With this, you can easily view the injector pulses, the crank trigger, and several other waveforms that come up in the diagnosis of problems. There are several pages of waveforms in the appendix of the WSM. I've found O-scopes very useful to diagnose electrical problems. Comes with CD application and users manual.

JD928_S4

Ok so new info... and I got it to START!!!!

The other day when I was testing everything I checked the temp II it reads 5.3 Ohms at about 34 degrees F so that seems to be fine. I could not believe it wouldnt start. When cranking I would smell gas so I figured it was just flooding itself out. I decided to unjump the fuel pump and crank a few times. 5-6 cranks later with my foot to the floor bam she popped and sputtered for a second. I then decided to crank and jump the fuel pump mid crank with my foot to the floor. I started and after 5 seconds of feathering it after she cleared out idled ok fine. I took out the jumper and quickly popped back in the relay and she kept running. It appears to run ok but just very very rich. I even moved it around in my parking lot. I walked away for 5 mins and let it run and everything is fine. So... It appears that something is causing it to run so rich that it would flood itself when starting but no so bad that it will continue to run when started. Any ideas? Maybe MAF?

Thanks again for everyones help!! It is truly appreciated.

Jacob

John Speake

Hi Jacob
I hope you mean 5.3k Ohms........ which would be OK at that temperature, 5,300 Ohms ?

If it still runs very rich over the range when up to normal temperature, then suspect the O2 sensor is bad.

JD928_S4

yea left out that little but very valuable thousand symbol k sorry. I will start it up again an let it get up to temp and see where things are. Thanks John

Regards,
Jacob

JD928_S4

So this weekend I spent some time and started the car by again cranking without the fuel pump jumped and jumping mid crank... started with some throttle feathering and ran a little rich for about 1-2 mins. I decided to brave an around the block trip that would up heading out on the highway and in total was about a half hour drive. At this whole time it ran fine! as if nothing had ever happened. I got home shut it off and let it sit for a few seconds. Then started it back up again without having to mess with the fuel relay. It started fine 3 times in a row. A few hours later I went out and same thing, it started right up. The only thing I can possibly think is that the temp II wasn't completing a circuit and after taking the plug on and off now has a good connection. Any other ideas? I am mind boggled. Again thank you everyone for your thoughts on this odd happening.

Jacob

Leslie 928 S2

SteveG

So then I would try to duplicate it by unhooking the Temp 2, etc.
Sometimes it just feels so good to KNOW you found the culprit. (and you know how to fix it.)