Going for first fire

Injectors: use a pick or jeweler's screwdriver to unclip the wire bale, careful not to lose it. Then the connector slides right off.

Ground reading, the 1321 is ohms? Weird! Try again with a booster cable clamped to the block and to battery (-). Maybe your chassis-to-engine ground is bad. Could explain a few things.
 
got low voltage at injector connection during cranking.....

coolant sensor test FAILED (so far). pin 13 of ECU to ground- no continuity, which means fail, I think, I have to go read the Hobbit to my 9 year old now, later....
 
Okay, I get a solid 1 on my ohm meter for pin 13 and ground (known good ground, straight to the battery). That's not right. Pulled the sensor and have 36 ohm resistance at the pins on it. Cleaned it up and boiled some water....still 36. That certainly isn't right. Could this little bugger be the cause of all my woes? I'd like to test it thoroughly before buying one, if possible.
 
I quick did test 24 and 25 and it passed both, so the guide says suspect the relay......okay.....hmmmm how often to relays fail?.
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With tests 24 and 25 both passing, we know that this half of the relay is working. We already verified the other half, so I think we can say the relay is not the problem.

now I'm questioning the ignition side again, maybe the dizzy is 180 degrees out or something?
Click to expand...

Listening to your your video clip, it sounds like the engine starts easy enough, so I doubt there is a problem with firing order or distributor 180° off.
 
Well, despite the coolant sensor being weird. The book still tells me that if the car fires and quits to do the relay tests. #24 passes now and test #25, which has you look for voltage on relay at 86b with AFM door open and closed. I got no voltage with the door shut but full 12.6 or so with it open. According to the test, this is proper therefore REPLACE the RELAY. Am I reading that right?
--Links removed because you can't link straight to the page--

BTW I redid resistance tests through the ECU connector for the AFM, all came back right in spec so I guess the AFM is good to go. This is from the last page of the guide, even though it doesn't say to do it through the ECU connection, that's how I took it. This page gives the range for resistance, not just the max.


I must have been typing while you posted, but it's a relay question still. The test results point to replace it. Does that make sense?

So.....I need a double relay??
 
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Am I reading that right?
Click to expand...

Nope. If test 24 (which measures the output from the relay) fails, and test 25 (which measures the input to the relay) passes, then relay is likely bad. You pass 24 and 25, so relay is fine.

If test 24 passes, the guide directs you to skip test 25 and go to test 26.
 
Sure could be the problem

36 Ohms is way low. With a working sensor, high temperature => low resistance. So in your case the ECU will not know that the engine is cold, and thus not enrich the mixture as needed.

I would also be worried about the engine grounding issue you found. did you get to the bottom of it?
 
Okay, right, 24 passes therefore 25 should be skipped, must read better.
I fiddled with the ground to the cam and it does give good reading now, might have been the rushed tester guy.

Okay, so maybe temp sensor than.....
 
Temperature sensor

A cheap ($0.99 + tax) test you can do is to replace the coolant temperature sensor with a 4.7 kOhm resistor (Radio Shack?). This will let the ECU believe you have a cold engine, and it should make the mixture rich enough to let the engine keep running.

Even cheaper would be to hold the AFM flap slightly open while you start the car. This will tell the ECU that more air is being inhaled that what the case really is, and it should inject more fuel to match. Just don't prop it open with anything that can be sucked into the engine :mallet:.

You are probably aware of this, but the car has 3 sensors related to temperature:

  1. Coolant temperature sender for the ECU.
  2. Thermo-time switch for the cold start valve.
  3. Temperature sender for the temp gauge in the dash.

Number 3 obviously has no effect on the engine. Number 2 only has an effect while you are cranking the starter (and even then only for a limited time and only if it is cold enough). Number 1 will affect idling and running while the engine is cold. I assume this is the one you are measuring.
 
Yes, I'm testing the coolant sensor, in the block by the spark plugs and dipstick. I did the test in the book, probe terminal 13 of the ECU and ground the other probe and I get infinity (test 5). Says to check wires, then if good replace sensor. Not sure how to test wires so I tried continuity from connector to pin 13, nothing with either one. Not knowing where these wires go (one must go to pin 13 I assume) I tested both sides of the connector to ground and got no resistance from either one. That is both are grounded. No idea what that means. I'll pick up a resistor. Maybe the ECU itself is bad?
 
Stop!

That is the coolant temp sender for the gauge.

The Temp Sensor is in the thermostat housing on the driver's side (transaxle end) of the block. It has two pins not one, and a white "F.I." connector.
 
Not the ECU temp sensor, for sure

That is the coolant temp sender for the gauge
Click to expand...

Or the thermo-time switch. Same neighborhood and it has two terminals like the ECU temperature sensor. The thermo-time switch is supposed to read 25 - 40 Ohms between the terminals at low temperatures (matches the 37 Ohm reading) and 50 - 80 Ohms at high temperatures. The switch should take place somewhere between 30°C and 40°C. (FI Guide).
 
Are you saying I'm mess'n with the wrong doo dad? That's funny.:mallet:

I was going by this;
coolant-temp-sensor.jpg


I think I played the "other" sensor before, found it a bit corroded and scraped at it. I will need to revisit that. The test at the ECU failed so I definitely should find the correct part at the other end.
I wish I were home so I could look at it.
 
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alright, I should be looking at the thermostat housing.
Anyone have a part number for the "coolandt temperature sensor"? Is the other a "coolant temperature sender". It seems I'm not the only one confusing these things....
I still plan on picking up a resistor at RadioShack in case I decide on "faking it" just to see what happens.
Maybe I'll finally luck out and the connector will be dislodged or something simple.....hey, I can dream can't I? I'm due for some good luck on this quest don'tcha think?
 
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Pulled the correct one, has 1760 ohms at room temp, put in hot water, went down to 900 by 160 degrees. So that seems fairly normal.
I have continuity between one of the pins at the sensor end and #13 at the ecu connector but from #13 to ground I get infinity and I'm not supposed to. The car is running a tad longer now. Maybe after all this it's an ignition thing.
Why wouldn't I get a good resistance reading between the ECU pin and ground. Hmmm
The sensor looked pretty good, maybe it was new and wrong? Grasping at straws here aren't I?
 
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Labeled incorrectly.

J that sensor in the manual is labeled incorectly. I went through that manual a dozen times and found a few errors. :read::read: I didn't feel confident enough to bring up the subject. So now I am fully convinsed. I did draw a bold line on that page, seperating the top and bottom as it is very confusing where it seperates. Should I meet some other X guys it was my intent to discuss this and a few other items in the manual as I only have my own experience to go by and am not a mechanic. I will now finally white out the ""coulant temperature sensor"" and relable it thermotimeswitch ,as I thaught it should be. Keep up the good work.
 
I think the thermo time switch is another entity entirely, isn't it?. I think the FI should be called a "coolant temp sensor" and the gauge one "coolant temp sender" or something.
So, what the heck's wrong with this thing?
Maybe just glogged injectors after all? I should pull one and see how it squirts maybe?
Back to the book.
I haven't played with the air temp sensor yet....I can break that yet a minute.
 
Maybe just glogged injectors after all? I should pull one and see how it squirts maybe?
Click to expand...

I wouldn't do that just yet. From your video it seems that the car starts quite easily, so it must be getting fuel somehow while you are cranking.

We know there is a problem with the Coolant Temperature Sensor wiring, I thing you should get that fixed first. The CTS should get ground via a wire that attaches to the left hand side of the valve cover. Does this ground seem to be clean and tight?
DSC09729M.jpg
 
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