Re: Help - 1986 5000cstq Suddenly Running Very Poorly

[Kiwi <enzeder@home.com>]

Hi Eric,

Check the fuel pump relay.  Actually, when mine failed, all it did was
cause the CIS Frequency Valve not to work, which you can hear pretty
clearly as a buzzing type sound from right next to the fuel distributor
(from under the fender).  I had the same (or very similar) symptoms that
you're having.

Scott Mockry has a great site for trouble shooting, and has these
directions for an "Output test" that will, among other things, test the
Freq Valve and do it while the engine is off making it easier to hear:
http://www.SJMAUTOTECHNIK.COM/ecuf.html#out1

I found that the center post of my fuel pump relay was wobbly (ie: no
connection).  Note that the two connectors that pass through to the fuse on
top of the relay will wobble, and it's normal.

Good Luck,
Arryn


At 08:04 PM 12/18/1999 -0500, you wrote:
>The 1986 5000cstq did not run well Thursday afternoon when I left work.
>
>It ran fine this morning driving into work.
>
>Seems to me that it is suddenly running really lean. 
>
>Symptoms after work: Started fine. Idled a little rough. Missed terribly 
>upon attempting to drive away. Almost died out then surged. Did not have 
>much ability to move itself. Stumbled with occasional knocking, even on 
>relatively low-effort acceleration. Ran a little better once warm, but 
>still not much power and stumbling with occasional knocking if pushed 
>harder than it liked, which was not very hard at all. I had to be really 
>gentle with it. There were no large hills on the trip home, but had there 
>been any hills it seemed that it would have caused terrible knocking and 
>stumbling. Was able to slowly work up into higher rpms (>4000) when taken 
>up gently enough. Boost gauge on dash shows pretty normal amounts of boost 
>for rpm. 
>
>Got home and pulled codes - 4444 - Nada.
>
>Cannot find any obvious hose leaks.
>
>Again, it seems really lean to me. 
>
>Where should I start looking? 
>Fuel pressure? 
>Vacuum hoses? 
>Some sensor? 
>Fuel pump (less than 3 months old)?
>Where?
>
>What could work fine driving into work and then act so wrong on my trip 
>home 9 hours later?
>
>I will greatly appreciate any help, BTDT, etc. 
>
>TIA,
>Eric R. Kissell
>1986 5000cstq, 1.8 bar, k24, not happy right now
>