new brickboard member here. I have searched the archives and have read the 700/900 FAQ.

thank you for taking the time to read my post, and i hope that you may have be able to help me.

i have a 1989 740 GLE with the B234F 16valve engine without EGR. i currently have what seems to be a switch that turns on the fuel pump. the car will not start without the switch engaged. i was told by my mechanic that this means that the ECU was bad and that this switch was a work around.

although this works, while i was on a trip last month, my check engine light went on at about 80mph (about 3.4K RPM). my usaul mechanic who is highly regarded here in Albuquerque, NM (Independent Volvo) told me that if it was still running fine i didn't have to worry about it, but to bring it in and he would run the diagnostic codes for me for free. well, i brought it in after i returned to albuquerque and he told me that he could not get the codes because of my ECU work around.

well, a new ECU would cost like 800 bucks, so unfortunately that's out of the question. the car's been driving fine around town without it, but i'm afraid of taking it out of town, it breaking down, and then needing to buy a new one for the 800 bucks out of town.

so meanwhile, i've been looking for an ECU, but they seem to be rare for the B234.

i looked at my part numbers are:

0 280 000 571 (bosch number i assume)
3507604 (volvo part number i assume)

i did some searching and one member found one at an ebay auction for 75.00

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=7904639970

however, here's where the confusion starts. i have talked to a couple of different recycled auto parts companies and they list a couple of different part numbers that they say would work in my car.

0 280 000 928 (out of a 1990 740 GLE B234)
0 280 000 563 (don't know which this is out of)
0 280 000 562 (listed on http://www.fcpgroton.com/fuel700900/volvo740b234f.htm)

now i am thoroughly confused. i only have about 100 bucks to spend and i can only hope to do this once, so I really need the right part number.

so a couple of questions:

1. is my mechanic being honest in saying that he needs a good ECU to pull diagnostic codes?

2. what is the right part number for my car? are there newer part numbers that will work that I just do not have?

thank you all in advance for your help. i need to get the old girl running strong again before a trip to California.

ps, my mechanic says i need an ECU w/o EGR