Injector cleaner

[Helirich]

Is there a favorite injector cleaner? Do you guys run it on some kind of schedule? Like once every 4 tanks?

I?ve been experiencing the engine stalling now and then. Mainly when I shift out of gear going fast and coasting to a stop light. Not sure if the cleaner will cure this. Going to give it a try.

[WHO1DMC]

I put a couple bottles of techron in about every other year. 10 years with no problems. It's getting about time to do it again.

I know some owners my do it more often but this has been my schedule.





Dave B.

[Timeless]

Pulling out of gear and coasting is a terrible idea. Never understood why people do that. I don't think a bottle of cleaner will resolve a K-Jet stalling issue.

[AugustneverEnds]

You probably can't do any harm with injection cleaner but I also doubt it will cure a stalling problem. Good luck!

[Helirich]

Pulling out of gear and coasting is a terrible idea. Never understood why people do that. I don't think a bottle of cleaner will resolve a K-Jet stalling issue.

Why is that a bad idea? The main reason I do it is to save the clutch. Brakes are easy and cheap to change. Not the clutch.

[David T]

If you drive the car regularly with fresh fuel it will keep the system clean. if you don't, a can of Techron occasionally is a good idea. Gasoline with Ethanol starts to go bad in as little as 6 months. Check for play (looseness) in the quadrant link between the throttle spool and the throttle arm. You also probably have vacuum leaks.

[Helirich]

If you drive the car regularly with fresh fuel it will keep the system clean. if you don't, a can of Techron occasionally is a good idea. Gasoline with Ethanol starts to go bad in as little as 6 months. Check for play (looseness) in the quadrant link between the throttle spool and the throttle arm. You also probably have vacuum leaks.

I almost never use ethanol. Probably do have a vacuum leak.

[mark w]

any fuel injector cleaner with PEA is recommended. Poly Ether Amine.

Techron Complete
Driven Injector defender
Liqui Moly DFI cleaner

and others by Gumout and AMSOIL



like others said, stalling is not something you can fix with a bottle of fuel cleaner.

[JohnZ]

Why is that a bad idea? The main reason I do it is to save the clutch. Brakes are easy and cheap to change. Not the clutch.

I second this and I'm genuinely interested in the answer! I do that from time to time, but not that much. Given that the load on the front brakes is massive downhill, I usually prefer to keep it under control.

[Helirich]

any fuel injector cleaner with PEA is recommended. Poly Ether Amine.

Techron Complete
Driven Injector defender
Liqui Moly DFI cleaner

and others by Gumout and AMSOIL



like others said, stalling is not something you can fix with a bottle of fuel cleaner.

The guy at the auto parts store recommended Lucas. I dumped it in and it might be better. It seems like it only stalls when I shift out of gear and immediately hit the brakes. If I coast for a bit and then brake, it doesn?t stall. When I let off the throttle, my engine slows down so much that my oil pressure light comes on for just a second. Then it picks up again to the idle speed. Apparently, if I brake during that moment, it will stall sometimes.

[Bitsyncmaster]

The guy at the auto parts store recommended Lucas. I dumped it in and it might be better. It seems like it only stalls when I shift out of gear and immediately hit the brakes. If I coast for a bit and then brake, it doesn?t stall. When I let off the throttle, my engine slows down so much that my oil pressure light comes on for just a second. Then it picks up again to the idle speed. Apparently, if I brake during that moment, it will stall sometimes.

Maybe your clutch is not fully releasing. I'm guessing you have a 5 speed. If you have an auto the converter does keep some load on the engine via drive train loads.

[David T]

Maybe your clutch is not fully releasing. I'm guessing you have a 5 speed. If you have an auto the converter does keep some load on the engine via drive train loads.

The decel valves on the throttle plates are meant to help prevent stalling. You can check that they move easily and the springs aren't burnt up. Many cars (not Deloreans) used a throttle jack, a device that slowly closes the throttle so it doesn't slam shut quickly causing the motor to stall. Not necessary on a Delorean with the idle motor controlling the idle BUT for it to work you can't have vacuum leaks. Vacuum leaks reduce the idle motor's effectiveness and mess up the A/F ratio. Not likely a dragging clutch.

[Helirich]

The decel valves on the throttle plates are meant to help prevent stalling. You can check that they move easily and the springs aren't burnt up. Many cars (not Deloreans) used a throttle jack, a device that slowly closes the throttle so it doesn't slam shut quickly causing the motor to stall. Not necessary on a Delorean with the idle motor controlling the idle BUT for it to work you can't have vacuum leaks. Vacuum leaks reduce the idle motor's effectiveness and mess up the A/F ratio. Not likely a dragging clutch.

I?m wondering if the vacuum brake adds to some other vacuum leak that causes the stall.

In any case, to day I ran into town and it didn?t stall once. When I dumped the Lucas injector cleaner in, I had a 1/4 tank. So it really got a strong dose of the cleaner. I filled it up when coming home. Maybe I just had a bad tank of gas. I have my fingers crossed.

[Rich]

I?m wondering if the vacuum brake adds to some other vacuum leak that causes the stall.

Very unlikely the brake booster is contributing to any lack of vacuum retention unless you're also noticing an increase in brake pedal force for a normal stop.

That said these cars are almost 45 years old so it's hard to rule stuff like that out.

If you really want to check for vac leaks in the brake boost system then find the brake servo tee in the engine bay, pull off the vac booster (servo) hose and pump it down with a brake bleeder vac pump/gauge. Stop at ~20inHg and see if it holds there for at least 5min. Easier than smoke testing that circuit.

[Helirich]

Very unlikely the brake booster is contributing to any lack of vacuum retention unless you're also noticing an increase in brake pedal force for a normal stop.

That said these cars are almost 45 years old so it's hard to rule stuff like that out.

If you really want to check for vac leaks in the brake boost system then find the brake servo tee in the engine bay, pull off the vac booster (servo) hose and pump it down with a brake bleeder vac pump/gauge. Stop at ~20inHg and see if it holds there for at least 5min. Easier than smoke testing that circuit.

Brakes work good.

[dn010]

Maybe the electrical load from the brakes coming on has something to do with it. I would check/clean the bulkhead connectors. Those are garbage in my opinion and I had many intermittent problems until I got rid of them. Also check the grounds in the area.

If it makes you feel any better, I have some difficulty shifting down into first or sometimes second gear while underway, so I sometimes need to coast to a stop as well. My daily beater is a 6-speed mustang. I typically try to downshift and use the engine to slow me down unless I have an asshole behind me, then I will coast and use the brakes so my brake lights are on, so I don't get rear ended. If I am in my neighborhood, I will coast to a stop so I don't annoy my neighbors with my loud exhaust on both the mustang and delorean.