2.0 16v Starting Problems

[ollie 0]

Hi,

I've recently aquired a 92 2.0 16v 'rado which had many problems when I got it which most have been sorted.

From cold it is a bitch to start and when it does is won't idle, almost like there is no "choke'. I've checked the 5th injector seems ok. Recently i've changed:

Cap

Rotor

Leads

Plugs

Cleaned engine earths

Cleaned ISV

Cleaned throttle body / intake

Also, sometimes the car refuses to start unless you floor the throttle when cranking it over. This has got less common since the above stuff was done but there's no pattern to when it does it. When its running its runs sweet as so I can't figure it out. Help!!!

 

Cheers

 

Ollie

 

PS its the old 9a engine

[Roger Blassberg 0]

There must be a water temperature input to the fuel injection/engine management, (via a sensor equivalent to the blue sensor on a VR6).

 

Best wishes

 

RB

[steve_16v 0]

I've had similar problem with mine recently, turns over on the starter motor fine but once it begins to fire up it struggles for a few seconds before it really gets going, although it idles perfectly well.

 

The radiator fan has been overly active as well, even if you move the car a few metres when its cold the fan will kick in few minutes after you turn the engine off. It also sometimes comes on when you disable the alarm and get in first thing in the morning :scratch:

[bcstudent 0]

Fuel enrichment on the 9A engine is via the differential pressure valve - the black lump on the engine side of the fuel distributor. Cold fuel enrichment is based on a temperature-controlled switch in the cylinder head. First, check the wiring to both. If all seems well remove the temperature switch and test its operation with a cup of boiling water and a multi-meter. If that's ok then the fault is likely to be with the differential pressure valve or the ECU itself.

 

The Haynes manual for the 1988 - 1991 Passat covers the 9A engine and gives tests for the differential pressure valve.

[ollie 0]

Thanks bcstudent I'll give that I try. Literally been tearing my hair out about it! Funnily enough its been better since the engine has been steam cleaned (it was a horrific oily mess when I got it. looked like an engine slasher movie!)

Watch this space!

 

Ollie