Plain Jane OEM nothing to see here rebuild

[vrracing]

Our RTek 2 shows the temperature reading from the ECU on the Palm. Does the 1.7 not have that capability?

[JustJeff]

I stepped away from the car out of frustration. Before I did that I tested the thermosensor at the ecu for both resistance and voltage. I couldn't test the lowest temp what with it being summer but the other temps checked out fine.

That same day I checked TPS and it's still good and at 1v. Took it for a drive and it seemed better idling but afr are still 10.8 at idle. Then between stops it developed worse idle and hot start issues. It did it 3 times and that's when I parked it for a week or so.

IIRC the IAT tested fine at the ECU. I'll look at my notes and also test it again, this time at the sensor.

I guess next up is to test AFM/MAF. One thing to note, I have a Cosmo AFM/MAF for a 13B. I'm assuming that could be a factor in the rich idle?

I have a spare set of coils to swap on in hopes of a magic bullet.

[JustJeff]

Here's the update and it couldn't happen in anyone else's build thread than mine.

I test my AFM and find that the IAT sensor within it is dead to the world. I have a spare N350 so I test it as good and pop it on. It's like night and day. Idle sounds much better. After a mile or so drive afr are sitting at 11.7 or so. I'm all happy and take it out for a long drive of blissful thoughts.

And then I burn up my EGI fuse a mile from home. I tried swapping bigger fuses just to get it home and burned up all of those. I ended up towing it home. So now I have to find my short. I've always been suspicious of the electronics in this car...and now I have some confirmation on it.

[vrracing]

Yes, the FSM refers to the connector I'm referring to as the "test connector" in chapter 4. If you search the club site for "initial set connector" you'll find lots of hits but it is referred to as "initial set coupler" as you can see in this thread.

And yes, you ground the ISC whenever you are adjusting your idle or setting your timing. Otherwise the ECU will fight with you.

Good to hear about the AFM. Bummer about the short.

[Pete_89T2]

Originally Posted by JustJeff

And then I burn up my EGI fuse a mile from home. I tried swapping bigger fuses just to get it home and burned up all of those. I ended up towing it home. So now I have to find my short. I've always been suspicious of the electronics in this car...and now I have some confirmation on it.

Definitly have a short. Look first for it in the areas you've messed with last. Sounds like you've spent lots of time under the hood and may have recently yanked the UIM a few times. One dumb mistake I made when removing the UIM was forgetting to reconnect the harness plug back into that ASV (air supply valve?). ASV is the PITA to get to one on the backside of the UIM, close to the firewall. When unconnected or not ziptied out of the way, that part of the harness is long enough to dangle down & hit the hot DP - instant 12VDC short on the EGI circuit when it hits the DP and melts the connector. In my case, the short was permanent since the melted plastic "welded" it to my DP, so it was pretty easy to find & figure out. If yours is just dangling, it might just be making intermittent contact as you drive around.

[JustJeff]

Thanks for the heads up on the ISC and about finding my short.

Its definitely an intermittent thing with the short. Last week when I started having hot start issues I noticed that one time the whole engine sputtered in mid drive. The whole engine lost power just for a split second but then kept on driving. That and the engine compartment has felt warmer than it should...specifically around the main fuses. Probably the short making contact then not, making contact then not. Probably heating up the fuses but not burning it.

Things I've recently messed with are the leaving my OEM O2 sensor wire unconnected. I'm using the simulated output on my Innovate and have it spliced in right at the ECU. But IIRC the OEM O2 wiring is a straight feed into the ECU. I don't think the O2 wiring routes through the main fuse.

I've been testing my TPS but that has all been back-probe.

I don't have an ASV on my engine, but I do have some harnesses dangling here and there.

[JustJeff]

I'm tapping into the green 6pin harness by the battery for my efan power. Does that feed into the EGI fuse?

[IMG][/IMG]

[RETed]

Originally Posted by JustJeff

I'm tapping into the green 6pin harness by the battery for my efan power. Does that feed into the EGI fuse?

Are you talking about MAIN power for your fan?

Most (effective) electric fans need at least 20A of current.
Almost nothing on the stock electrical system can support that kinda current with the exception of the starter...
I will run dedicated power wires for electrical fans.
Minimum 10-gauge wiring and as short as possible - through a relay.


-Ted

[JustJeff]

Sorry I should have been more clear. Here's the diagram I used for the efan

[JustJeff]

At least when the enigne is warming up the EGI fuse is fine. Popped a new one on, let it idle and warm up to about 170 and nothing to speak of. main fuses box isn't getting warm at all.

My idea had been to rig up a test light to plug into the EGI fuse location. I figure as long as there is a short the light is going to, well...light up. If I get in and start looking around and the light goes out while I'm handling something...well that would tell me the source of my problem.

If it's an intermittent problem, that makes my idea much more difficult. Any ideas how to proceed would be wonderful.

For what it's worth the engine sounds fantastic with the N350 AFM on....that's a plus.

[JustJeff]

Here is what I have found from looking at wiring diagrams about my EGI fuse. I have +12v IGN power for the efan tapped into the B1-08 Check Connector. The green 6pin. That harness sees current via the EGI fuse which goes through the Main Relay.

The only time I've had a problem with the EGI fuse is when I had the efan manually switched on for an extended period of time.

Forgive my ignorance with electrical...I know just enough to be dangerous...
Ted you mentioned using the starter for power. Are you thinking having fused/breakered power coming from the starter rather than the battery. Or the IGN?

One thing to note from that diagram. I have not yet tapped into 1O pin for idle.

[JustJeff]

Well, now I've done it. I read about using a resetting fuse and a compass to track down where my short is. Only problem was the resetting fuse was resetting too quickly and melted the insulation.

The plus side is that I found where my short was. It was like I suspected. The +12v for the efan which was plugged into the test connector by the battery. That wire got pinched under the battery tray and rubbed till it had exposed wire. The melted wiring stopped exactly at that point moving towards the relay for the efan.

Though it did not stop traveling down the harness side. It followed the wiring diagram perfectly, getting all melty along the way. It went from the 6pin (B1-08) through to the main relay (B1-02) and on to the EGI fuse harness.

I started cutting into the harness to trace it back. It looks like the damage is isolated to just main relay harness, check connector wiring and harness and EGI fuse wiring and harness. I'll do more digging tomorrow morning. My biggest concern is that from B1-08 harness following the B/W wire back it then split. I haven't traced it back physically but I have looked at the diagrams. It's going to both the Main Relay (B1-02) as well as to (X-11) on the passenger side kick panel.

At least from the digging I've done so far and looking at the diagrams..it's looking like I"m better off running new wiring than trying to replace the entire harness. It looks like that harness covers a lot of ground. Going from firewall on driver side (I'm assuming ending at the driver kickpanel?), across the front of the bumper and ending by the passenger side headlight.

Lesson learned, now to fix my mistake...

[JustJeff]

So I dug around in my wiring and the damage isn't too bad. Gonna replace the Main Relay, gonna source new harness for the main relay and a new Check Connector. I don't really need the Check Connector as it's only used for my efan, but while replacing things I might as well make that look pretty.

[JustJeff]

Finally got around to fixing the wiring. It's starts up and idles quite nicely. Next things on the plate, recharging the A/C, making a cold air intake box, deciding if I'm doing anything else with the body...and paint.

[vrracing]

Gratz. It must be a relief to clear that hurdle