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I bought it cheap because "it doesn't run right", so I'm taking it step by step to fix. Right now it runs rough, when it goes to closed loop it idles like crap (surging up and down), and exhaust smells rich. All symptoms of bad injectors, I just want to make sue I conducted the test correctly.
I bought it cheap because "it doesn't run right", so I'm taking it step by step to fix. Right now it runs rough, when it goes to closed loop it idles like crap (surging up and down), and exhaust smells rich. All symptoms of bad injectors, I just want to make sue I conducted the test correctly.
You conducted half a test and that is being generous. Warm and cold could make a difference in the test. Even if you did cover both, you still don't know whether the flow rate is right or the spray pattern. So like I said, half a test is generous for what you did. Misleading at worst, meaningless at best.
IF I am looking at it right, you have junk for injectors. They are Multec if I am correct. Toss them in the garbage can and get reman 24pph from FIC and install. Get new gaskets for the intake manifold. While you are at it, take the TB apart and clean the passages. That means top plate, IAC, IAC housing and the TB comes off. Do the coolant bypass while you are at it. Clean passages, spray brake cleaner on the pintile of the IAC and wipe GENTLY. Reassemble with new gaskets and reset the IAC. I WOULD NOT DO THE FSM METHOD. Use a scanner.
I'd get their reman injectors where they have cleaned, tested and changed the basket filter. I had a set of injectors that I couldn't feel anything wrong while they were in the car. Tests showed different. Sent them to FIC and they called me back to ask if I had extra high pressure. Seems like one of the basket filters had collapsed enough to hurt the flow significantly. They replaced the basket filter and sent it all back. I tested the returned product again and my numbers agreed with their numbers before and after. Kinda proves to me that they did the work they said they did. As the Russian Proverb goes "Trust but Verify". Glad to say that I tested and FIC was NOT found wanting. Besides, it is easy to spend money with:
ive never heard of so many injectors being off at once.
hipefully they are multecs. that would explain it.
if not, id be wondering why 3 are shorted and looking for clues as to why.
cheers.
All 8 or 9 injectors get the same fuel. IDK about Canada but around here it is very hard to get fuel without ethanol. AVGAS or Marina Fuel and neither is cheap or easily available. Even regular gas stations compared, Costco is about 40 cents a gallon cheaper so unless I have some crazy influence, getting pure gas will be neither cheap nor easy.
Might as well change it all at this time to gas that can tolerate ethanol. True, it is 10% but Multecs are fuel cooled so.... Either change it today or tomorrow. Might as well be today. Eliminate that problem and if he cleans the TB, we can see what else is wrong. Air leak or spark or fuel pressure.
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Originally Posted by aklim
IF I am looking at it right, you have junk for injectors. They are Multec if I am correct. Toss them in the garbage can and get reman 24pph from FIC and install. Get new gaskets for the intake manifold. While you are at it, take the TB apart and clean the passages. That means top plate, IAC, IAC housing and the TB comes off. Do the coolant bypass while you are at it. Clean passages, spray brake cleaner on the pintile of the IAC and wipe GENTLY. Reassemble with new gaskets and reset the IAC. I WOULD NOT DO THE FSM METHOD. Use a scanner.
Though I'm not sure on the size for a 1990. There are some differences between years. I wouldn't be surprised if Aklim is quoting the right size for a 1990. Really, it doesn't matter because FIC will send the size most appropriate for the ECM in the 90.
I recognize those as the OEM multecs....same as the ones I replaced 10 years ago! I had several THAT bad on my 89 in 2007...with only 50k miles. FIC says multecs weren't made to handle alcohol (ethanol) and I believe it.
The resistance is indicative of the coils shorting thought I don't THINK 5-6ohms is FULLY shorted yet. That's how it can still "work". Kinda....Poorly...at least from the garage to the curb. LOL
To be honest, I've never learned much about how the SD systems deal with variances such as this...but I'm fairly sure the computers allow for 15% +/- fueling error. So, as the coils "short out" and work less efficiently, the ECM can "tell them" to stay open longer/shorter.
Coils are magnets that setup a field about a moving piece of metal. In this case, the valve that opens/closes the injector. I'm guessing a partially shorted coil creates a lower field (vs no field). That's how the injector can still have some "valve" function.
I was thinking OEM was 16ohms...but maybe 90 was different? In any case, you absolutely need to swap injectors due to the small sampling (in the video) and the age of the car.
Fair warning: This is where I starting tearing into mine in 2007. When it was FINALLY back together 3 yrs later, it was a whole new engine (383) with a block from a different setup (4-bolt truck).
We'll, I have contacted FIC, they should be emailing me back tomorrow. Yes, they are multecs and are original to the car (81,000 miles). I've decided, based largely on your collective advice/expertise, to get a set of remanufactored injectors, probably Bosch iii. Thanks for all of your help...you guys rock!
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