I've never replied to one of these before so hopefully this works.
I had similar problems with my 95, ~89k miles. Would have really weird
sometimes non existent throttle response at just light throttle cruising.
Progressed into dying a couple of times when coming to a stop. Also when
warming up as it was crossing into closed loop would stutter and idle
Decided it was a good time to dig into the valley and do all the normal
stuff in there as I've never done it and I could at least take all of that
out of the equation, cleaned drain, new coils, all connections good,
Haibeck chip, no more secondaries, new wires, plugs, injector housing
gaskets and o rings.
This didn't change anything. Had also ordered new O2 sensors. Replaced the
passenger side. Was not able to get the driver's side to budge and no real
room to get any type of good leverage up in there. She runs 90% better with
just the passenger side replaced. Still just a little idle stumble as the
coolant reaches about 120 degrees.
On Mon, Apr 30, 2018, 14:14 Marc Randolph <[log in to unmask]> wrote:
> Howdy all,
> I'll start with my questions, then provide the back-story:
> 1. What are people using as a modern Diacom replacement? modern PC or
> Android preferred. Real-time graphing capability would nice, but the
> main point is logging, possibly graphing it later.
> 2. Any ideas on what might cause a surging problem that goes away
> AFTER the ignition is cycled when the car is fully warmed up?
> With my daughter now of driving age, I've loaned my daily driver to
> her and have started driving the ZR-1 every day. And yes, she's asked
> multiple times if she can drive it to school (or anywhere) by herself
> - looks like I've created a monster by making her learn to drive a
> Anyway, 2 months ago it started driving worse. I found several
> injectors were bad, so I replaced them all. That mostly fixed the
> problem, but I had introduced two new ones. I pulled the plenum again
> and found where (on the previous pull) I had broken a brittle vacuum
> hose and somehow loosened a plug wire from its coil. So fixed all
> that and now it ran good. Ended up replacing spark plugs also.
> So... new plugs and new primary injectors and it runs like a top for a
> month or two. Last week, in the middle of the drive to work, it
> started mildly surging. During light throttle (to maintain speed...
> RPM's in the 1500 to 2000 range), it would feel like it's losing
> power, than suddenly it's not, then losing, then not. At a stop, the
> idle sometimes (but not always) wanders from the normal 675 RPM up to
> 1000 RPM - and sometimes as high as 1200 RPM. It seems to get worse
> as the car is warming up, so I'm imagining all kinds of things. I
> pull over and turn the car off - don't see or smell anything weird.
> So I fire it back up, and .... the problems are gone.
> I've repeated this several times now and it's pretty consistent - when
> the problem starts occurring, I can cycle the ignition and the problem
> goes away... ASSUMING the car has been running long enough. And once
> it's gone, it stays gone until it cools way down. Not sure what the
> threshold is yet (hence the need for a Diacom-like software).
> Good ol'dad suggested he's had a similar behavior on a different car
> with a bad temperature sensor. But those seem to be functioning
> properly. I do wonder about the O2 sensors though...
> Idle speculation welcome!
> TOPICS: TECH or SALOON
> Problems? Contact ZR1Mom at: [log in to unmask]
> ZR-1 Store @ http://www.zr1net.net
> ZR-1 Saloon Keeper
TOPICS: TECH or SALOON
Problems? Contact ZR1Mom at: [log in to unmask]
ZR-1 Store @ http://www.zr1net.net
ZR-1 Saloon Keeper