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Jetta Problems (1990)

Have a Jetta that dies out when I accelerate… it’s one of those cars with wires running everywhere and has been worked on by mechanics like Homar Simpson… HELP Me Please!!!

Have a fuel pressure test done (at different rpms).

First, find a shop that doesn’t employ Homer Simpson.

Dying on acceleration is typically a sign of insufficient fuel being delivered when the throttle plate opens up and suddenly huge amounts of air are allowed to be pulled into the cylinders by the pistons.

One possible cause is poor fuel pressure (volume) available (RR’s fuel pressure test is an excellent place to start) due to a weak pump, a clogged filter, (a) clogged injector(s), a bad fuel pressure regulator, and a few other details.

Another possible cause is a missing or bad sensor signal from one of the sensors that monitors your engine’s fuel demands and tells the ECU to open up the injector(s). You have a number of these that measure your airflow in and compare it with the pressure change in your intake manifold )when you stomp the pedal), monitor the oxygen level of the exhaust (this one is a low probability IMHO) and even mobitor the physical position of the throttle. If one of these sensor signals is bad the computer may not have all the information it needs to know to open the injector pulses longer.

There are ignition system possibilities, but like RR I’d start with the fuel system and engine demand sensors.

This ain’t rocket science. A good shop should be able to diagnose the problem.