Sputtering accelaration ONLY during first 3 seconds of driving.

[Marlon Targa 86]

I have a 1986 3.2 engine. I live in Southern Cali.

- I start the car. No problems. Starts right away... always.
- idles fine
- When I drive off, there is a hesitation for a couple seconds. I loose power for a split second, then it goes back to normal
- After that everything is and stays fine
- Some days (maybe 10% of the time), the hesitation is not there. I'd like to think on warmer days. But I haven't been able to confirm the pattern on when the hesitation doesn't happen.

Any clues?

Marlon

[masterdave]

some things you may want to check out are,

-Fuel pressure/leaks in fuel lines
-All of your injectors, if im not mistaken the 86 has the bosch system
-Drastic move would be to check the timing but i doubt thats it
-Air filter, may be dirty
-I had some hesitation on acceleration issue that was a result of a bad distributor cap and rotor, they were all burnt up. It was a nice and cheap fix and solved the issue right away.
-I dont know much about the bosch motronic system on these cars, i have a 78, but it should have a crank or cam sensor, that may be having issues.
-Fuel tank clog, you may be starving it of gas some where in the fuel system.

These are just general things that come to mind.

Best
Dave

[Marlon Targa 86]

Thank you. I'll keep all those in mind.

Seems weird it only manifests itself as I drive off after starting the car.
Maybe it's a vacuum leak that fixes itself when the engine heats up?

Originally Posted by masterdave

some things you may want to check out are,

-Fuel pressure/leaks in fuel lines
-All of your injectors, if im not mistaken the 86 has the bosch system
-Drastic move would be to check the timing but i doubt thats it
-Air filter, may be dirty
-I had some hesitation on acceleration issue that was a result of a bad distributor cap and rotor, they were all burnt up. It was a nice and cheap fix and solved the issue right away.
-I dont know much about the bosch motronic system on these cars, i have a 78, but it should have a crank or cam sensor, that may be having issues.
-Fuel tank clog, you may be starving it of gas some where in the fuel system.

These are just general things that come to mind.

Best
Dave

[nameisbauer]

I have the exact same issue. I will take the suggestions too, thanks

[djcdmv]

Subscribed... I always attributed this to not being warmed up yet. Will be interesting to get everyone's opinion.

[Tippy]

Your car is pretty low miles, but the Motronic system is supposed to adjust to sensor degradation (when sensors start changing parameters/outputs due to age) with higher miles up to a point.

The only thing I can think of that degrades with age, not just miles would be any rubber components in the intake tract/circuit.

I think you may just have a simple vacuum leak and it is the easiest to check for since these cars are very old now. I'd try some starter fluid on all of the vacuum lines and rubber components around the intake and see if the idle raises.

If it does, there is a leak.

I don't think it is ignition related IMO from your description but I could be wrong.

If that is not the issue, I would then check the Cylinder Head Temp sensor resistance (need a shop manual or do a search on how to check). This tells the ECU if the engine needs additional fuel for cool/cold start-ups.

The CHTS also can be a single-wire and most here recommend to change out if it is. I'd do a search on this anyways.

Lastly, if the two above are not it, you might consider getting a air/fuel ratio check and have someone adjust the AFR since it may be on the lean side.

Keep us posted and if you fix it, PLEASE LET US KNOW!

[Drisump]

Try a hit or two of Techron, I had this issue earlier in the season and that seems to have sorted it out. Apparently the injectors in this car are quite sensitive to fuel quality and will build up deposits causing sticking and compromised low RPM performance. Cheers