The Saga continues...more issues

[Jalisurr]

Hey folks,

So I recently discovered that, surprise surprise, the injectors on my car needed replacing. The guy I bought it from said they had been replaced with new Bosches, I guess those went bad too because I had two of them with ~6 Ohms.

So I pulled the plenum and installed all new Accel injectors, put it all back together and took it for a short test ride and it seemed great! Faster than ever and very smooth.

However, now, a week later I took it for a bit longer ride and it started running quite badly again. I was sitting in traffic for a little while at the start of the drive and then when I got to the highway on ramp and floored it it just stumbled and hesitated. Did a little more driving around then got scared and went home :( it was stumbling right off idle and also if I gave it any more than about 5% throttle.

Got it back to my garage and popped the hood, it smelled and felt really hot in there, and then I could hear what sounded like bubbling coming from the throttle body I think. I didn't see the coolant gauge go above probably 220ish, but I don't know.

When I did the plenum pull I only drained a little coolant, just enough to get it below the throttle body.

Looking for more of your infinite wisdom, coolant issues? Something leaking? Is it overheating and that's why it's running poorly? Or do you suspect something else and I'm barking up the wrong tree?

[lisounds]

maybe a air pocket in the coolant???

[XfireZ51]

Maybe fuel pump(s)

[oricale]

Any Codes?

The car may have gone into limp mode. Disconnect the battery for a few, check coolant, vacuum lines and try again. also check those injector wires.

[Jalisurr]

Nope, no codes. I'd love to see some codes, at least I'd know what was going on.

I'll try resetting the ECU, that's a good idea. And check all the injector wires.

[W i l l]

Check the resistance of the new Accel injectors...with the engine warm. Perhaps one of them stuck open.

[Pete]

If it does it when hot Ohm/check coils
How old are the wires.
Be very careful with coolant air pockets
You sure it was 220?
If ECM sees too high Temp
It will shut down secondaries.

Pete

[HAWAIIZR-1]

maybe a air pocket in the coolant???

I'm with lisounds and Pete suspecting an air pocket with the described sound. I would jack it up on the passenger side with the cap open to see if there is the gurgling and an air pocket release. If not confirmed about the actual temp like Pete mentioned.

[Dynomite]

When you fire it up cold the Injector Housing Coolant Manifolds should get warm within a minute. If not...the coolant is not circulating (Air Locked Water Pump). Prolly not relevant if your short and longer ride was more than a mile or so as by then you should be at least half way on the temperature or more. But.....also depends on what the Outside Air Temperature was in Vancouver.

[Demps]

Everyone's points are spot on. If it's none of these...

Another consideration, what plenum gaskets did you use?
1) is the plenum torqued to spec?
2) anything inhibiting proper mating?
3) depending on gasket, is the coolant passage hole in the front where it is supposed to be?
4) are there indications of coolant getting into cylinder? (Smell, plugs steam cleaned, visible coolant)

Ted

[Jalisurr]

Thanks for the suggestions all,

I ran the car for a bit the other day with the coolant cap off (though I didn't have it jacked up). The injector housings did get warm very quickly, so coolant does seem to be circulating. I did get some air bubbles coming out the coolant cap though, so I'll try running it with the side jacked up and see if I get some more.

I used the plenum gaskets from jerry's gaskets...I'm pretty sure I got them the right way around. There's no obvious coolant leaking out, but I'll pull the plugs next to the coolant tubes and see what they look like. Is there any other easy way to tell if coolant is getting into cylinders? I did torque the plenum to 19ft-lbs in the tightening sequence from the manual.

I'm sure it got higher than 200, but I'm just going off the gauge in the dash, so I don't know the exact number.

Thanks for the ideas, guys.

[Jalisurr]

Hey guys, update on this.

Tried jacking up the passenger side and getting some air out. Definitely got some bubbles come out but nothing massive. Coolant was definitely flowing properly, all the right hoses got warm. I also tried resetting the ECU, but that didn't change anything

Doesn't seem like the issue is only when the car is warm, it was definitely doing weird things cold as well. At idle it sounds like it occasionally (like once every second or two) misses. And then just off idle there's hesitation.

I noticed an air hissing noise from the drivers side of the plenum near the throttle...so I'm thinking maybe a vacuum line came loose while I was driving? That'll be the next thing I check, but want to see what you guys think.