I just bought a 1991 GTA 350 a couple of weeks ago. It runs well but has a slight hesitation when stomping the throttle. The previous owner said he replaced 1 of the injectors and suggested the others may need to go as well.

I did a resistance check on all 8 injectors. 7 of them tested at 14.9-15.0 ohms. One injector tested at 16.1 ohms. Is this one injector out-of-range and showing signs of going bad? Or is that injector good and the others are going bad? I do have a refurb set of Bosch III injectors waiting to go in. Just curious as to the resistance values.

 

They really should be pretty much the same across the board. If you have a set of bosch lll's do yourself a favor and install them. Do you have a stock intake? If you do you're going to have to double up on the orings on the bottom of the injectors or you can send them to us and we'll apply our adapter to the bottom.

 

I do have the stock intake. The Bosch came with the doubled o-rings installed.

I was curious as to whether 7 are going bad or just the one. Hopefully I will have these new injectors installed in the next week.

Thanks for the input SouthBay. What would be the cost to have the adapters installed? Or I guess I don't need to worry about since they have the additional o-rings anyway.

 

if you already have the double orings you really don't need the adapter. However, if
you wanted them I would give them to you at no charge to you.

 

That is great. I finally have some time tomorrow. I'm going to tear into this to get those swapped. I appreciate the offer for the adapters. If having the double o-rings is just as well, I'm going to install them as they are. This is my first TPI engine. I'm sure I will have more questions at some point later on.

Out of curiosity, would the 16 ohm injector be the potentially bad or good one? That was the point of my post originally. thanks.

 

For reference, my Bosh III's ohm out at around 14.7, so probably the 7 are in the correct range. It might depend on the brand though, I haven't had the opportunity to ohm too many brands for comparison.

 

The injextors of the 7 are good, but remember to leave the car warmed up prior to doing TV test? Of the test remains the same. 80% the 16oms is dumping to mucj fuel into it, like the other guy states here, they all need to read the same amount,

I also had the same issue, I had 5 working to about 15.2 and all other was at 15.9 to 16.2, so it was not running right, called our lady in Florida where we all get out fuel injextors, ( forgot the name there) she send me a matched set and car ran good for the nezt 4 years, this was a while ago,

If u invest into injextorsike your doing, brag a fuel regulator, it's a helpful thing for our cars, also throw in some good fuel additives, it won't hurt when you install the new set,
Good luck with your car,
John

 

Thanks guys. That's the best info I have gotten. Even searching through here about this subject. I knew they all need to be within the same range. Just wasn't sure about the tolerance between the injectors. It makes sense that one injector would be dumping more fuel. The car seemed to be running a little rich.

I will post how the car runs after the injector swap.

 

Status update:

Replaced the injectors with the Bosch III. I noticed the previous owner installed a BBK afpr. Good to go there. I have not check the pressure. I left it as it was set. I will need to check it in the next couple of days. This car is my daily driver.

I have issues working on any car due to a bad back. Damn scoliosis.

I took the car out for a short drive. No hesitation, no gas smell. Best of all, the car now kicks the backend out with ease. Acceleration is much improved and runs so much smoother now. It wasn't horrible before. Just enough to know something wasn't right.

Thanks for the responses and info from everyone. I do need to resolve some vacuum lines. Looks like some weren't connected previously. Only 1 open port on the plenum. I plugged the hose with a screw to avoid vacuum leaks.

 

good job. Happy things worked out