[Slider]

Concern is to eliminate Oil leaks and getting confident that I won't get a “Pop” (backfire) from having run the main fuel pump by hot wire while it was connected to and sending gas to the fuel rail.
Any advice is welcome-

I suspect Oil leaks from:
Distributor O ring – went to replace it and noticed quite a bit of play in the bottom of the distributor, have read about this on the site but not sure I want to go the new dist route yet.

Oil Separator – I had cleaned this out last year and a few chunks of the brass came out, read all about it and have not come to a conclusion on what’s the best approach to take with it. Blew out the small hose returning to the Oil dipstick, there was only a little oil.

Charcoal Canister (Behind Passenger Fender): Have removed it since the smoke from the “Pop” appeared to come from one of the (2) hoses connected to it. I will be replacing the hoses. The can is really heavy, no liquid comes out, I was thinking during jumping the Main fuel pump it feed gas into the vapor lines and so may have gotten in there.

Cam Cover gasket: passenger side front shows some sign of minor leakage. May be ordering new gaskets for this. From what I been reading (doing too much of that and not enough work) a clogged Oil Separator can cause an increase in pressure on the gaskets causing leaks.

Other:
I had removed the Air Plenum to get to difficult to clean ground wires and to dry out the plenum in case it was holding fuel from jumping the main fuel pump. I did not find much evidence of gas in there just Oil in the rubber sleeves feeding off the plenum, thought I’d find a mess of carbon but I’ve had worse in other vehicles. Historicaly I do get a lot of carbon out the exhaust pipe.

Had disconnected and vented the vapor line feeding the expansion tank in the trunk because I was getting that nasty fuel tank clunking and have been running like that for about 5 years. The venting solved this issue.
Injectors: All tested good on resistance (2 ohms each). Still want to get them in for bench testing and cleaning.

 

[Slider]

Any thoughts ?

 

[Tifosi]

What year car?

 

[ghnl]

Concern is... having run the main fuel pump by hot wire while it was connected to and sending gas to the fuel rail.

Under normal operations the fuel pumps run continuously. Fuel is supplied to the fuel rail under pressure, the regulator controls the fuel pressure in the fuel rail and diverts any excess back to the tank.

The 'concern' would be if you were in an accident. The engine might stall but a hot wired fuel pump would continue to pump fuel - perhaps leaking it out and feeding a fire...!

 

[Tifosi]

Carb'd and EFI is continuous running but I thought SPICA cars had a little switch that cut power to the pump when in decelerate mode?

 

[ghnl]

Presumably L-jetronic.

1985 Spider

I will start a new thread called Oil leaks and Jumped Main Fuel Pump

 

[Slider]

It is Stock 85 Spider-

The pump runs continuously but does the fuel relay reduce the voltage to the pump via a signal directly or indirectly from the ECU which might lower the pressure to the rail when less fuel volume is needed?

If not seems I should not be concerned about damage to the pressure regualtor.

When I jumped the Pump I think I disconnected the Fuel relay because I was concerned about putting too much voltage where it might not belong.
Was grasping at straws when I did that and grasping for more here to gain some assurance that I didn’t screw something up, the popping sound (like a backfire or big fuse pop) was a bit scary.

 

[Tifosi]

The pump runs continuously but does the fuel relay reduce the voltage to the pump via a signal directly or indirectly from the ECU which might lower the pressure to the rail when less fuel volume is needed?

Nope, pressure is delt with exclusively by the regulator and the ECU mearly determines how long or short the injectors are pulsed open.

When a load is put on, the ECU changes rate accordingly and the pressure climbs a bit to help ensure volume levels are maintained.

If not seems I should not be concerned about damage to the pressure regualtor

No concern at all unless it's got pressure too low (lean condition) or too high (rich condition)
Plug chop won't neccisarily tell the truth either as the EFI tries to keep 14:1 A/F ratio when not loaded or idling, so the plugs are gonna look awful lean regardless.
Pressure must be checked with a gauge, and if there's serious doubt even if pressure checks OK, then a volume test should also be conducted.

The sweet spot for pressure is in the 32~36psi range in general, 42~46psi when under load or upon initial throttle floorage, and dips down into the mid 20's when the throttle is at WFO then dropped rapidly back to idle.

When I jumped the Pump I think I disconnected the Fuel relay because I was concerned about putting too much voltage where it might not belong.

12V DC system with little variation throughout the setup.
VVT gets reduced down to about 8V when the current goes through that bit on the end of the harness plug, but otherwise, 12V for the pumps, fuel sender, etc, etc.

Was grasping at straws when I did that and grasping for more here to gain some assurance that I didn’t screw something up, the popping sound (like a backfire or big fuse pop) was a bit scary.

Backfire on decel/rapid throttle release in the EFI cars is generally more relevant to one of two things: the TPS is not hitting it idle position switch due to index or fault of the switch, or, there's an air leak in the exhaust somewhere that's sumping in a jet of cold air when the pipes go -ive pressure on throttle release which in turn causes any unburned fuel residue to ignite in a loud and volumous fashion.

In a very general way, the further forward an exhaust leak is, the higher the probability that it'll make pops as the gasses are still very close to thier combustion point as opposed to further downstream where things have cooled considerably so the jet of air doesn't push things over the edge.

 

[Slider]

Okay I got my injectors back and put it all back together, tightened headers a bit (I had problems with gaskets in the past but not for at least (3) years since I built my own ‘super gaskets') but have to yet to add coolant.
After a struggle she ran with sputtering and eventually settled down to a fair idle after a couple of shut downs and restarts.
It does exhibit a rich smell and will backfire a bit.
Before diving into checking fuel pressure which seems okay since she’s running, I will be looking at vacuum lines as I do hear some vacuum leak that sounds like the line from the brake servo.
The Auxiliary Air Valve is not good (does not close or open complete).
Also wondering about the VVT and how much of an effect that could have on the backfiring, there is a fair amount of oil on it, could the VVT keep the exhaust valves from closing completely and cause backfiring?

 

[Tifosi]

VVT only effects the intake side and only advances the cam when active.
It won't effect lift or duration but does have a small effect on overlap.

Nothing that would cause backfire or the like though.

 

[Slider]

Can the Vacuum from Servo have effect on backfiring?

Since I do not have the coolant full I presume the Coolant sensor can't not give a reading, does it need to send one during cold start and can't do it without coolant?

I know the engine never got anywhere near where the Tstat would need to open but if the Coolant Sensor had this effect I will fill the system complete, just trying to avoid it since I'm starting to suspect the Oil Port at the Water pump may have become clogged.

 

[Tifosi]

Any false air leak can create issues.

In regard to the coolant sensor, its quite possible that its having an effect because its not reading anything more than ambient temperature, which in turn causes the ECU to beleive the engine is running very cold, so it in turn enriches the mixture to whatever level it feels is correct for the given readings its getting.

Upon initial startup its unlikely to be that radical, but subsequent warmer starts/running can end up being ignorantly rich because the ECU is thinking 'enrich for 50 degrees' and the engine is begging for 'lean out for 100 degrees'.

There's also the cold start temp sensor to consider (thermo time switch) as it deals with actual startup enrichment. The colder it is, the longer it helps keep the CSI open to give that nice fat cold start mixture.

Whether either could cause things to go so rich that it would create the issues you describe, I dunno as I wouldn't start an engine without coolant anyway for anything more than a moment or two just to be sure it actually ran.