Ed MD

I replace the old/original relays with new ones, now the car will turn over and fire but not run. After searching the archives, I'm still at a loss. This is my 85S US that ran like 'a bat out f hell' the week before without any problems.
Here is a list of what I've done/checked:

All the relays have been checked by replacing them with the horn relay,
the fuel pump works when the relay is jumped, and there is power to the injectors,
I've jumped the LH(XXV) relay, and the fuel (XX)relay and the EZ (XVI)relay,
I've borrowed a computer LH/EZ from another car, '86S,
I loosened the panel and checked the connection,
I've checked all the fuses,
I've charged the battery,
I've checked all the grounds, all the positive connections on the relays,
I've checked for spark, also checked to make sure that it wasn't flooded.
I've checked to make sure it has gas,

Any sugestions?
Ed Meier

Mrmerlin

Put the old relays back in as you do this make sure that all of the connectors in the CE panel are in their slots as one may have pushed out the other side

Ed MD

Already did this.

Alan

What relays did you use to replace them all? - you say all the relays have been checked by replacing them with the horn relay... what do you mean? they aren't all like the horn relay...?

Check all the fuses

Alan

Ed MD

They are #53 relays. I'm going to redo the fuses again. Ed

worf928

Make sure that you have the correct relays in the correct sockets. Then double-check that you have the correct relays in the correct sockets. Make sure that the sockets marked as unused are in fact unused.

Bill Ball

If you have checked for spark and fuel delivery, then something is probably preventing the injectors from firing. Are the spark plugs dry? If so, that is further evidence fuel isn't making it out of the rails.

I would do this...spray something like carb cleaner or starter fluid (ether) very briefly down the intake throat. If the car then starts briefly, you know the basic failure is in the injectors (again, assuming there is good fuel pressure in the rails). Could be a shorted injector harness plug wire.

ARCFLEMING

Ed,

I'm watching this thread with interest ,because I'm having the same thing happening to me. I've changed all related relays including fuel pump (and had electrical system tested), and fuel and ignition computer (relays).The ignition computer was recently rebuilt and fuel injection computer inspected and tested (no help). The next step will be to replace crank position sensor and temp sensor II as some people have mentioned on other threads.

Brian
86.5

Ed MD

When I checked the individual terminals, with relays LH(XXV),FP(XX),EZF(XVI)..there is no signal to initiate the FP relay(at terminal 85 & 86) when the car is being cranked but there is a pulse when the car is initially turned on. I placed a noid lamp on one of the FI "plug" and it did not light up.

ARCFLEMING

Ed,

Maybe related? Ignition control unit (from another thread) part # 928 602 706 01 928 Int. web site.

Brian
86.5

Bill Ball

The LH sends the signal to the FP relay pin 85. Did you verify that all pin 30s on the relavent relays have 12V (key can be off)?

Ed MD

Verified that the 30 terminal has 12 volts.

Tampa 928s

I'm not sure you were clear but why did you decide to replace the relays, were you having problems?

Do you have a manual, "by using a meter"; if so there are several test points that can be used to see what is not getting power.

If the car ran fine then it is something you caused, do you have a relay and fuse chart?

Ed MD

She's the Garage Queen and a friend left his 928 while he was gone for several weeks. I was trying to deal with another no-start problem with his car and took out the relays because I knew they were good. I used the modified paint can opener to pull the relays. I ordered new relays to replace these and when I installed them....no start. Could I have shorted the LH by using the paint can openers to pry the relays off? I also checked the harness as per Dr. Bob, these is an open circuit at pin 18 on the LH connector (from the "official fuel injector thread"). And yes I have a relay chart and new relays. Ed

linderpat

Did you disconnect the ground strap in back before pulling the relays? If not, a short to the LH could have occured.