Checking Injectors (with ID's)

CHECKING FOR LEAKING INJECTORS

We will start by describing what you are looking for.

You will be looking to see what the flow looks like to start. It should be a nice, crisp firing in a good conical pattern. If there is a break in the conical discharge there is foreign matter in the injector. If it is more of a constant fog the injector is stuck open. If there is an irregular firing pattern or no firing at all, the injector is sticking closed or there is a bad connection at the pig tail.

Which is which?

The primary injector ( grey or black ) is the one nearest the drivers side fender. It is the smaller of the two injectors.
The secondary ( blue or green ) is the one towards the OVCP. It is the larger of the two injectors.

part #......ID..From...To.....Description
MD614102 L 6/86-89 580cc, Primary, black, Driver Side of TB
MD614036 M 6/86-89 1080cc, Secondary, Green/blue, Pass
MD614114 K 2/86-5/86 850cc (2 Required)
MD614004 J 2/85-1/86 850cc (2 Required)
MD608869 ? Thru 5/83 850cc (2 Required)

Checking injector performance.

You need to get the car warmed up preferably. Once there, remove the OVCP (over valve cover pipe) and you will be able to see the bottoms of the injectors. You will be looking for any condensation or drips on the injectors. If there is drips you have leaky injectors.
This next step is easier with a helping hand. Unplug the coil wire so she don’t try and start on you. Unplug the secondary injector ( nearest the OVCP ). Have someone turn over the motor while you look into the TB with a light and watch the spray pattern. Once done turning over, watch for drips. Now, unplug the primary injector and plug it into the secondary. Repeat the cranking and watching.

This will tell you what shape the injectors are in. Remember these are 20 YO cars. I would also recommend putting a new set of “pigtails” on the injectors due to the old ones get corroded and maintain a poor connection.

I will be adding links to injectors, cleaning services and pig tails in this thread too as I come across them.


www.Witchhunter.com Injector cleaning

Bosch or Motormite part #85850. "Bosch replacement FI pigtail"
General FI pigtail #35730 or PS35730
Standard FI pigtail #sk25 or s-654