10 replies to this topic

[Lilgreenmini]

Hi all,

 

I have a completely rebuilt (1 year ago) Spi Auto (injection) with aftermarket Aircon.

 

It's keeps conking out after about 15 mins / 3 miles. It just fades, like someone kill switched the car.

 

It then won't start for about 5-15 mins, and pulling random fuses seems to help sometimes.

 

I have brand new spark plugs in there which are gapped to 0.35 and compression test is good. Temp gets up to about 200.

 

Can anyone suggest a checklist of what it could be?

 

I'm wondering of the coil is bad? Could it be vacuum lines getting hot (I have silicon, no hard lines or elbows)?

 

Could it be something else electrical? Fuel pump?

 

 

Halp!

[NLinPEN]

I would suspect (but this is just a guess) that it has to do with fuel supply to the engine. Assuming that you have sufficient fuel in the tank it could either be a bad fuel pump, a clogged fuel filter, or a leak in the lines. If fuel is leaking I think that you would be able to smell it. Replacing the fuel filter is something that often gets ignored because the nuts tend to corrode and are difficult to undo without causing damage to the lines.

[Ethel]

Carry a plug spanner to check if it still sparks when cranked - you could pull a lead, but you'll get a better view with the plugs out & know it's strong enough to jump the plug gap & you might whiff if there's fuel. It's a wet manifold system, so it shouldn't die quite as abruptly if it is fuel.

 

Can you hear the fuel pump?

[Lilgreenmini]

I would suspect (but this is just a guess) that it has to do with fuel supply to the engine. Assuming that you have sufficient fuel in the tank it could either be a bad fuel pump, a clogged fuel filter, or a leak in the lines. If fuel is leaking I think that you would be able to smell it. Replacing the fuel filter is something that often gets ignored because the nuts tend to corrode and are difficult to undo without causing damage to the lines.

 

Thanks, I just find it weird it's always after 15 mins and only when warmed up. Talk is more than half full. I don't really smell fuel except a bit in the cabin when driving which I'm told is normal for these?

[Lilgreenmini]

Carry a plug spanner to check if it still sparks when cranked - you could pull a lead, but you'll get a better view with the plugs out & know it's strong enough to jump the plug gap & you might whiff if there's fuel. It's a wet manifold system, so it shouldn't die quite as abruptly if it is fuel.

 

Can you hear the fuel pump?

 

Thanks! I would pull the plug when it dies and see if there's a spark but I'm inclined to just replace the coil to take spark out of the equation, shouldn't cost much.

 

Wouldn't know what the fuel pump sounds like to be honest as my exhaust isn't exactly quiet but leaning away from it being a fuel issue as it's like I instantly lose power. It seems electrical rather than fuel.

Edited by Lilgreenmini, 30 March 2026 - 08:52 PM.

[Ethel]

If you turn the ignition on, without immediately starting the engine, you should be able to the pump kick in. Yours is inside the fuel tank.

[NLinPEN]

 

Thanks, I just find it weird it's always after 15 mins and only when warmed up. Talk is more than half full. I don't really smell fuel except a bit in the cabin when driving which I'm told is normal for these?

 

Have you tried to open the fuel tank cap after the car has stopped? I wonder whether a vacuum has been created inside the tank. That could make it harder for the fuel pump to work?
 

[coopertaz]

as suggested check for spark first when it has died you need to work out whether fuel or spark first. if no spark is coil hot? if spark ok can you hear pump running in tank? if both these ok then fuel filter or less likely gauze on fuel pump pickup could be causing starvation.

[Lilgreenmini]

Thanks people!

 

I have a new coil and fuel filter arriving today becuase unlike nearly evey other part of the car that was new as of a year ago, I don't know how old those two are as they came form the previous owner. Also it seems there was a racing Pertronix coil (maybe a 3ohm) and my mini mechanics (sadly in another state) said they're crap and better to go with the a genuine DLB198 coil (0.9ohm).

 

Will report back in case this helps others in the future......

 

And otherwise it's on the fuel pump!

[68+86auto]

A few basic tests would be much cheaper and quicker than throwing parts at it.

 

Does it have spark when it won't start?

 

Does it have fuel when it won't start?

 

 

Spray starting fluid into the intake. If it has no fuel but has spark, it will now run.

 

 

There are so many things which could cause this issue and without testing you could be replacing lots of parts.

[PeterG]

Check your o2 sensor. They start in open loop and go closed loop when warm enough. If there is a problem as soon as it goes closed loop the engine will die. Had this on my SPI, changed to HIF44.