Chrysler and the Move to Fuel Injection and Turbochargers
The first use of electronic fuel injection was a system similar to modern EFI setups; it was created by Bendix and first installed on Chrysler cars. The system was a disaster, and it was quickly replaced by carburetors on nearly all the fuel injected cars; Bendix sold the patents to Bosch, which essentially waited for materials and computer technology to catch up.
One may ask why fuel injection was not used earlier in the 1980s; in the United States, for example, Volkswagen implemented multiple point injection on its mass-market Rabbits in 1979, with great success. Burton Bouwkamp wrote:
This is hindsight - and is only my opinion. Our engineering effort on fuel injection was inadequate - it was at a "hobby" level rather than at a "development" level. The primary reasons were engineering budget problems (Chrysler was run by "bean counters" from 1962 through 1978); and we did not have a “champion” for fuel injection (a VP, an Engineering Director, or a Chief Engineer).
The 1958 and 1981-83 [Imperial] experiences certainly dampened whatever spark there was within the company for fuel injection. Bendix had a good mechanical system in production in Europe and we should have adapted that design to our engines. [Throttle body fuel injection was added to the 2.2 liter engine in 1984, the same year the multiple-port injected, turbocharged 2.2 liter engine debuted.]
As you know we kept leaning out and leaning out the carburetor to meet ever more stringent emission standards until the engine didn't run very well. It frequently took several engine restarts to back our 1985 cars out of the driveway in the morning.
The Imperial, Chrysler’s first modern car with fuel injection, had a troublesome system, that probably would have worked well with more testing up front. As Marcos wrote:
A low pressure electric pump in the tank supplied fuel to a high pressure control pump. The speed of the control pump determined the quantity of fuel injected and was controlled by the computer by varying the voltage.
Fuel was injected by a spray bar assembly. The regulator had 2 tubes coming out of it on each side, which jutted out over the throttle openings, and each bar had 2 fuel openings over each throttle plate (for a total of 8). There was a "low-speed" spray bar which worked up to about 30psi, and the fuel openings had brass nozzles on them to promote a fine spray. Above 30psi, the regulator opened to send fuel to the "high-speed" fuel bar. The openings were just pinholes, and delivered fuel in a stream, but it was said that the velocity of the air going through provided enough atomization.
In principle, it was a simple system. A mass air (not manifold pressure) sensor found the quantity of air being ingested. The computer drives the pump and an optical flow meter on the outlet provides a feedback signal to control the air-fuel ratio. The o2 sensor provides further feedback for fine tuning, and a means of calibration for open loop modes. Temperature sensors for the air and fuel provided adjustment as needed, and the distributor pickup and throttle position sensors provided for certain modes of operation. Since there is no manifold pressure sensor, the fuel board calculates this.
This system was plagued by electrical issues, mainly due to the somewhat primitive design and crude components. The biggest complaints were stalling or no-start. The auto shutdown relay was prone to being tripped by electrical noise. Due to being mass-air-sensed through the air cleaner snorkel, it was very sensitive to vacuum leaks. Corroded connectors and grounds caused lots of issues over the years.
When they run, they run very well, much better and smoother than the 2bbl 318s of the time. They incorporated several physical features around the throttle butterflies and throats to improve fuel atomization. These cars were capable of pretty decent fuel economy.
The system was not used for later cars. Instead, Chrysler dropped the mass air sensor and set up a different system for its 2.2 and 2.5 liter engines. Over the next few years, carburetors would be systematically replaced by fuel injection. As Burton Bouwkamp wrote:
The throttle-body (TBI) EFI [used by Chrysler on all non-turbocharged engines in early years] was certainly not anywhere close to port injection, but it gave a better control of the air-fuel ratio than did the trusty old carburetor. In fact, the principal reason we all wanted to get rid of TBI was the number of calibrations which would not have been needed with MP [multiple port] EFI. It was always a cost vs. quality argument and I imagine the decision was made at a much higher level.
If there had been an airflow meter available then which gave accurate and repeatable measurements, we might have been able to sell it to management. With TBI, fuel-air distribution was essentially the same as a carburetor, and a new calibration was needed for every engine-car combination.
Turbochargers were used to bring Chrysler’s ubiquitous four-cylinders up to V6 power, cutting the need for Mitsubishi imports and allowing more power in smaller cars. Pete wrote:
Working with the turbo was fun but I would have preferred to do a Rootes Type supercharger. I argued the point as far up as I felt comfortable but TURBO was a magical word at that time at Chrysler. Ford (GT) and GM have both proven me right but that don't help much. We had a unit, from Eaton, but I couldn't even get permission to do a quick 'n' dirty job with it.
He added later:
I was the guy responsible for the performance of the 2.2 and later 2.5 turbos. We had no one in-house who knew much more than the very basics. It was pretty much learn as you go. The electronics folks at Chrysler were not any better off. Engine designers had one thing right; mount the turbocharger as close as possible to the exhaust manifold to reduce heat losses.
We learned a lot about turbocharging and, yes, the 2.2 responded to everything we did.
Our biggest difficulties lay with detonation, or the detonation sensor which was, I think, unreliable. Given this, the specified fuel could not be regular octane. I fought this battle and eventually won something in the owners' manual saying better performance and longer life could result from the use of high octane fuels. This was a big breakthrough. I had several different turbo lease cars and they were fine; they never tasted low octane fuel.
As to Mitsubishi, they became the production source sometime after my retirement. And up till then, their only contact with us was regarding their turbos and nothing to do with future designs.