[chucksurette]

I haven't posted here for some time, as my Astro has been running GREAT!

But lately it has had a HARD START issue. Initially fuel pressure was good, so I replaced ignition cap & rotor and took the van for a 1200 mile ride, towing a camper. Everything was going great - until it died...

Around the time it died, starting may have been a little harder than normal and it did stumble and die once on me.

Checks on the roadside showed ZERO fuel pressure at the rail. No sound of pump initializing at all. CHECK GUAGES light on dash. Manual cited this as possible pressure switch issue.

Assuming pump failure - Fuel pump replaced and after that did nothing - Oil pressure sender replaced.

Turning the key on gives no initial pump prime. Extended cranking - same still no pressure at rail.

Current codes - 147 (02 bank 1 sensor 3) 401 (egr recirc flow insuff) 452 (EVAP press low)

From past experience with missfires, I checked connections to fuel pump and 02 sensor with tank on ground - and it fired up! When tank put back in place - NOTHING. Back to square one.

My thought was a bad wire coming back to pump - because of INTERMITTANT fault - but watched AstroWills video on the relay circuit and I'm wondering how far off I am.

Tools on hand - fuel pressure gage, OBD II scanner, FLUKE multimeter, M/L service manual. Any advice where to start searching for voltage appreciated. Glad my van made it all the way from Ontario Canada to Florida before dying....

 

[chucksurette]

More thoughts - when van died - oil pressure gage went wonky and remained pinned. Check gages light came on, and is still on.

 

[chucksurette]

1998 Astro - sorry

 

[chucksurette]

The plot thickens: Before tearing into things I decided to pull connectors and shake wires on O2 sensor and main plug back to fuel pump. Turned key on and I had fuel pressure and IT FIRED RIGHT UP. I guess I am looking for a bad wire...

 

[tungtide]

Good ending

 

[chucksurette]

Good ending

I hope so. I went back under the van and pulled the connector for O2 and 10 pin connector at what looks like a vapor canister (?) That connector was WET. Water dripped out when I opened it. I left everything open for a few hours and put it back together an hour ago. CHECK GAGES light is out, but the codes for egr and knock sensor remain. I'll keep an eye on that. The water probably came from Sunday night, I had to pull over on the highway twice because it was raining harder than my wipers could handle. I didn't spot any chafed wires today and I bought some new loom and re-clamped everything and zip tied anywhere that had any play.

I can't say that the problem is solved, but the symptoms have cleared for the moment.

 

[AstroWill]

I mean even if it's not 100% solved, you are on the right track.

 

[chucksurette]

Thanks Will.
I am very happy with the van so far - no complaints.
Very happy that it got me 1200 miles to Florida before acting up.

Test drive to the gas station today to see how things go.

 

[chucksurette]

I had some time with a test light yesterday and found the ECM is not supplying the 5v reference to EGR valve... There is continuity from point to point. The manual says replace ECM at this point. Van still runs, current code is EGR.
Thoughts?

 

[AstroWill]

I had some time with a test light yesterday and found the ECM is not supplying the 5v reference to EGR valve... There is continuity from point to point. The manual says replace ECM at this point. Van still runs, current code is EGR.
Thoughts?

Continuity isn't the best test, a voltage drop test with a load would be better. Is it outputting 5v reference at the PCM? All power inputs to the PCM getting proper voltage?

 

[chucksurette]

Tested egr across a-e, with a light, per manual. No light. Checked the red wire e for continuity with the ecm connector and it was good.

Tell me more about test with load.

 

[AstroWill]

5v reference is D, grey wire on my wiring diagram, not the red wire. Would also affect MAP sensor and fuel tank pressure sensor.