PCM diode?

[RichardP]

Hey guys.....my car would turn over,and attempt to start but it bogged down, and stopped. Occasionally this would happen all i needed was a jump-start to the battery, and i'd be fine for a month or so. I figured because it was a valu-craft battery..that the battery would be the problem. However, today my car died twice so i figured a new battery was in order.I got to the store ,and accidentally turned the car off so there I could not get it to start again.The battery however read a good charge,but I had it replaced with a better battery anyway.So we get the battery in there, and again the car would start, bogggggg down, and die. When whitey showed up we started going through the fuses/relays, and accidentally he pulled the PCM diode thinking it might have been a fuse puller. When he put it back in we heard the fuel pump finally prime. and some clicking, and the car maraudelessly started. Any idea on why this is happening/happened? Could it be that the contacts are corroded? Anyone else have these series of unfortunate events.

[Zack]

You can check it with a multimeter on ohms or diode setting
It will only pass voltage in one direction if it's good

[whitey]

I checked the ohms at 200, either direction, it still had full resistance, i however totally forgot about the diode setting. I understand the diode only allowing the flow of electricity one direction, but what are the odds of the diode failing intermittently? I know when leds fail....it just fails, to the point of no return. Me and rich were thinking its the plug on the fuse box that was corroded, and although there wasn't amps(i think) in a single battery to jump/arc through the corrosion, the hot shots people gave him made the electric jump through it....and once it bridged the gap, regular power was able to continue to flow. This is all just theory so if you think its wrong, im all ears!

[whitey]

Another thing to note, which may or may not have to do with anything is the car threw a code, which i believe was p1004, rich can you verify this? And when i hooked up my scangauge2, the fuel pressure was not getting a reading. His is a 300b, mine is 300a, and i can read fuel pressure with the sg2. We originally thought the fuel pump was going up, and although we didn't have a gauge to see pressure, there was pressure in the fuel rail from manually (ball point pen) depressing the schrader valve.

[RichardP]

Whitey.....P0190 which the shop manual stated was the fuel rail pressure switch. This is only a byproduct of the pcm malfunction i believe.

[whitey]

Steve.....P0190 which the shop manual stated was the fuel rail pressure switch. This is only a byproduct of the pcm malfunction i believe.

Dont you ever call me my real name on here, they could be watching...:eek:

[RichardP]

huh????????? :)