Eagle Repair: Eagle Talon Engine Problem, mass flow sensor, mass air flow sensor

Question
My son has an 1990 Eagle Talon TSI, Turbo.  We bought it from someone that hadn't driven it for two to three years because it wouldn't start.  We found out that it didn't have much compression so we took the head off and found that the valves were in bad condition.  We sent the head to a machine shop and had it completely rebuilt. We installed a new turbo charger,new waste gate,new air mass flow sensor, spark plugs, a new exhaust manifold, fuel filter, injectors, timing belt and hose.  Each time we connect the air mass flow sensor wire, it misses terribly and dark black smoke comes from the exhaust.  When we unhook it, it doesn't miss as bad but still miss.  The compression on the cylinders are cylinder 1 (150 psi), cylinder 2 (140 psi), cylinder 3 (150 psi) and cylinder 4 (150 psi).  What do think is the problem?  Could it be the electronic control module?  If so, how would we check that?  

Answer
Even though the MASS air flow sensor is NEW, Does not GUARANTEE that it is 100% operational. I have seen many of these sensors and others that were defective right out of the box. Have you considered that someone else was given this sensor and may have damaged it unvisibly and returned it to where it was purchased and guess who got it now ?.

Since all it is is basically a for ease of words a type of thermometer of which sends an electrical signal, as would a potentiometer, back to the computer.

The ONLY actual way that you are going to know for sure is to install one from a correctly running vehicle.

I have many times had to try several supposidly NEW ones in order to find one that is 100% operational.

Does the CHECK ENGINE light on the dash ever illuminate and what code(s) and what are there meanings ?.

I retired in 89 and can only rely on past experience and or have the vehicle accessible to me.

In  rae cases the LOGIC module was the problem, But not always.

With it setting for 2 years, you are going to have to manually test each and every circuit and relay within the complete electronic system of the vehicle.

This will require a FACTORY SERVICE MANUAL(S) and a lot of testing and patience.

Service manuals just like you dealer gets can be purchased by contacting a company called HELMS. They have a website.




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