My mechanics have had the car for weeks and can't figure this out. I have an '89 Formula 305tpi/5spd. Here are the symptoms: idled smooth, but no power at all and wouldn't rev above 4k rpm. The longer I drove it, the lower the rpm limit became until it hit 1k rpm. Started the car the next day to drive to mechanic and same thing all over again, but it got worse faster. Now, it won't idle at all. No codes when running, a stream of codes not running with key on, fuel pressure and pulse to injectors seems OK. New computer did not fix the problem, but now at least they are getting codes when running. They disconnected 2 of the injectors and got it to idle but still can't figure it out.
Has anyone seen this before? Any suggestions? Any help would be greatly appreciated.

 

Yea, I can’t believe your shop can’t figure it out; you wasted money on the ECM. Your car has the crappy multec injectors and they are starting to short out and lowering the injector impedance. By unplugging the injectors you are raising the impedance of the injector circuit causing it to fire the remaining injectors correctly. this is an easy fix, get on eBay and buy a set of 19lb svo injectors and be done with it.

P.S You can check each injector with an ohm meter and tell which ones are bad, anything under 11 ohms I would be replacing.

http://cgi.ebay.com/ebaymotors/Fuel-...QQcmdZViewItem

 

I thank you very, very much for your help. I'll be on ebay tonight!

 

To elaborate:

With the injectors having lower impedance, it allows more current to flow through the ECM injector drivers. This overheats them and shuts them down.

edit:

I would still test them before going out and buying new!

 

Thanks, I got on my impedance rant, and forgot to mention the lower impedence is overheating and shutting down the injector drivers in the ECM

 

So, the injector drivers should be tested first? I'm not familiar with injector drivers. Are they replaceable? I have the original '89 service manual. Is the info on testing the drivers in there?
If the injectors are starting to short out, shouldn't they be replaced anyway? I'm assuming that they should be replaced in sets and not individually.
They are the original injectors with about 75k miles on them. The car is started regularly, but not driven very often.

 

The injector drivers are simply power transistors in the ECM. You can't replace them easily. (if you happen to be an electrical engineer it should be easy)

Just test the impedance of the injectors with the multimeter.

Any below 12 will cause problems. Normal is 14-17 ohms.

 

i was reading your post on this subject cause i have a set of injectors i just got off a guy and i wanted to test them. after reading this i did and they all read 16.8-17.0 except 1 it reads 12.5 does that mean that injector is going to go bad soon thanks

 

I would say it was on its way out, the coils are starting to short together.

 

ok thanks i will replace the bad one