Hi everyone..
please help.
i have purchased a Transam 1989 fire bird.
engine starts but smell to much fuel in my exhaust.
i think that i have a TPI 305 engine (where can i read that?)
is it useful to have a OBD1 scanner?
i have changed airflow sensor
i have changed spark plug
i have changed sparkplug cables
i cannot drive, because of the fuel that is getting into my cylinders.
i have burn one time all sparkplugs already.
maybe someone can help me with the steps, how to recognize my engine and the steps to help me with this problem

 

Sounds like you have one or more leaking injectors.

 

Leaking injectors could cause a lot of your issues here is a thread about testing for it
https://www.thirdgen.org/forums/tpi/...injectors.html

Is the car in factory configuration or has it been modified?

Your VIN number should tell you if it is a 305 or 350 but you can also look at the casting numbers they are stamped on he block behind the head on the right side while looking at the motor

 

Fuel pressure regulator could also be leaking. Easy enough to check. Pull the vacuum line off it and see if there's fuel in it after running

 

Hi all,

Thanks for the replies.
I have checked. it is a 305 TPI.
It is not modified as far as the old owner told me. it was bought standard, but the owner is a old guy. so to much information from him is not possible.
is there any other way to check the leaking injector one by one? then to check with a gauge.
and if the pressure regulator had a problem, i think i would have a engine that would give problems with starting.
its start pretty good.
the only problem is that after 50- 60 seconds. it doesn't idle good anymore, because of to much fuel coming into the cylinders.
and it starts to smell.
i have burned already one set of sparkplugs.

 

The gauge is by far the easiest method. Other than pulling the rail while connected and making a huge mess / fire hazard, I suppose you could send the injectors to a shop with the equipment to test them on a bench.Try to avoid making assumptions. If you think something is happening, or not happening, you must test it. Otherwise, you don't really know anything for sure.

 

As Komet said if you take out the plugs while still attached to the rail and then turn the key to prime the system but not start the car you'll see them leak, I just did this test yesterday myself as I'm in the process of replacing injectors and wanted to know for sure they were leaking and indeed I had two that continued to drip fuel after priming.
You can get a good cheap fuel pressure gauge off ebay, I did to test mine, I strongly believed I had leaking injectors because I use a tonne of fuel and it smells very rich.

 

Try taking a long flathead screwdriver, pushing the flathead against each injector while the engine is running, and listen for a persistent and consistent crisp clicking sound of the injector solenoids. (A mechanic's stethoscope would only do this job better.) It should rise and fall with engine RPM. Listen to each injector and if you hear any outliers making their own beat, or they sound squishy then BAM that's a bad injector. if you would like to poke around with a multi-meter you can also ohm out the injectors. reading should be around 13-18 ohms. its more important for the injector resistances to be consistent between injectors than it is for them to be a specific value (AS LONG AS THEY WERE ALL INSTALLED/REPLACED TOGETHER IN THE PAST. if not, then the resistance method of checking for bad ones is unreliable.) any outliers are likely stinky traitors to the cause of keeping these cars on the road. checking the pressure regulator is also important, so you should do that as well, just make sure you don't smell gas coming out the vacuum line, and verify that there is fuel pressure by sticking something pointy in the schrader valve on the passenger side fuel rail. (wouldn't recommend starting the car for 24 hours if you do this, so if you need to get going fast, just buy a fuel pressure gauge at autobone.) also, DO NOT BUY AN OBD1 SCAN TOOL THEY ARE ALL RIPOFFS. they all function by just jumpering pins on the ALDL connector like you would with a paperclip. Back in the day, specialized scan tools were available to dealerships and tuning shops who wanted to shell out the money for live data diagnostics. If you want that, buy one of these: https://reddevilriver.com/aldl.html
word of advice, the USB version of these cables works pretty spottily with the 1227165 MAF sensor ECM. so you might have to reconnect often with those, but the later 16198259 style ECM is a direct equivalent and does not have these communication problems. (You have an '89, so you might have a MAP sensor ECM) Vacuum leaks in the wrong places are also known to cause these cars to run rich.
I also should have said this at the beginning of my post, but make sure the car has a catalytic converter before complaining about gassy exhaust. cutting the cat off these cars will not cause the ECM to throw a code. (check engine light)
Hope this helps.

 

Excessive fuel in the exhaust can also be caused by a bad throttle position sensor (TPS). Easy to check to see if it is bad with a volt meter.