injector resistance
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Joined: Jan 2013
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From: Friendly WV
injector resistance
I've found another vac leak and it idles smooth now but still has a bit of a hesitation-stumble just off idle. I cleaned the injectors but it's still there. My motor shows 190K but was rebuilt 20-30K ago. It feels a bit like an injector to me. I've been told I can read the resistance on the injectors to help determine which is bad. What value am I looking for?
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From: Friendly WV
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From: Hartford WI
At their age, it don't think it will be a bad idea to replace them with Bosch III reman ones since they have been flow tested already.
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From: Friendly WV
I can't say I have ever seen it work so IDK. I send mine out every 3 years for cleaning and testing. I have test results of before and after which helps determine the next cleaning cycle. I am not sure about ATF in the tank or how it affects the injectors which are already sensitive to too much ethanol.
At their age, it don't think it will be a bad idea to replace them with Bosch III reman ones since they have been flow tested already.
At their age, it don't think it will be a bad idea to replace them with Bosch III reman ones since they have been flow tested already.
Team Owner
Joined: Jul 2004
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From: Hartford WI
I had bought this car to flip but we liked it. At this point I'm trying to fix everything that's wrong but in a way that's as affordable as I can. As for the ATF, it's old school. You always want to use the old style fluid too, none of the new stuff. back in the day, the big three would dump a qt of ATF into the tanks on the assembly line, SOP. It's just a lite, high detergent oil, and it works wonders on old carbs and injectors. My vehicles all get a pt every 6mos or so.
Besides, if you suspect injectors, I would have them tested so I can see the spray pattern and volume. Try asking a local tech college if they have a flow bench for injectors. If not, I would send them out for testing just to eliminate a problem. I'd prefer getting a reman set if it were me since I know those injectors are old and not ethanol resistant.
I haven't used any of the old school techniques so I wouldn't know how well it works. I don't work on carburetors and farm those out when it has problems. Personally, I am not a fan of dumping stuff in a tank in hopes that it gets everything clean. To me it is like cleaning a room in the dark. Never know how much more needs to be cleaned. YMMV but for $15 an injector, it would be good to know how they flow and spray.
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From: Friendly WV
It would depend on how long you are trying to keep it. I don't plan to sell my car so I did the injectors. Multecs are not great with ethanol and most every place doesn't sell ethanol free gas so that would be something that had to be done.
Besides, if you suspect injectors, I would have them tested so I can see the spray pattern and volume. Try asking a local tech college if they have a flow bench for injectors. If not, I would send them out for testing just to eliminate a problem. I'd prefer getting a reman set if it were me since I know those injectors are old and not ethanol resistant.
I haven't used any of the old school techniques so I wouldn't know how well it works. I don't work on carburetors and farm those out when it has problems. Personally, I am not a fan of dumping stuff in a tank in hopes that it gets everything clean. To me it is like cleaning a room in the dark. Never know how much more needs to be cleaned. YMMV but for $15 an injector, it would be good to know how they flow and spray.
Besides, if you suspect injectors, I would have them tested so I can see the spray pattern and volume. Try asking a local tech college if they have a flow bench for injectors. If not, I would send them out for testing just to eliminate a problem. I'd prefer getting a reman set if it were me since I know those injectors are old and not ethanol resistant.
I haven't used any of the old school techniques so I wouldn't know how well it works. I don't work on carburetors and farm those out when it has problems. Personally, I am not a fan of dumping stuff in a tank in hopes that it gets everything clean. To me it is like cleaning a room in the dark. Never know how much more needs to be cleaned. YMMV but for $15 an injector, it would be good to know how they flow and spray.
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From: Hartford WI
Kinda why I asked if you were keeping it. Im not shy about going over budget if it saves me more aggravating times diwn the toad. Multec injectors aren't the greatest things since sliced bread so I'd dump them so I don't have to worry for a while. It sucks to spend more than budget but saving aggravation is good.
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From: Friendly WV
Kinda why I asked if you were keeping it. Im not shy about going over budget if it saves me more aggravating times diwn the toad. Multec injectors aren't the greatest things since sliced bread so I'd dump them so I don't have to worry for a while. It sucks to spend more than budget but saving aggravation is good.
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From: Hartford WI
Clean all passages and give it a light lube. Make sure that the blades are smooth when you open them like you would with the go pedal.
Now that all passages are clean, reassemble. Try find yourself a scanner and sit in the car with the engine off but key in run. SLOWLY depress the go pedal and see if the TPS voltage goes up smoothly. If not, you are probably out $120 for a TPS from Mr Goodwrench. Not sure who else makes a decent TPS but don't get a junkyard one.
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From: Friendly WV
If you can't swing the injectors now, lets try something a little different. Again, it can't hurt and it is something you probably must do anyways. Remove the Throttle Body and clean it up. Remove the IAC motor and the IAC housing. Clean all passages. DO NOT reuse the paper gaskets. I treat them like condoms. I don't reuse either.
Clean all passages and give it a light lube. Make sure that the blades are smooth when you open them like you would with the go pedal.
Now that all passages are clean, reassemble. Try find yourself a scanner and sit in the car with the engine off but key in run. SLOWLY depress the go pedal and see if the TPS voltage goes up smoothly. If not, you are probably out $120 for a TPS from Mr Goodwrench. Not sure who else makes a decent TPS but don't get a junkyard one.
Clean all passages and give it a light lube. Make sure that the blades are smooth when you open them like you would with the go pedal.
Now that all passages are clean, reassemble. Try find yourself a scanner and sit in the car with the engine off but key in run. SLOWLY depress the go pedal and see if the TPS voltage goes up smoothly. If not, you are probably out $120 for a TPS from Mr Goodwrench. Not sure who else makes a decent TPS but don't get a junkyard one.
This evening I pulled the coil wires off the EGR solenoid and it seemed to help some. A few min later, it stalled out. Nothing is consistent. It does seem to run better WO the EGR sol hooked up though. But, I still have that stupid hesitation. GRRRRR! This is the kind of thing that will bug me till I get it. I will too.
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From: Summerland B.C. Canada
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From: Friendly WV
No. Honestly, I'm way out of my comfort zone. I have to stop and think hard about everything that's going on in this system and there's so much I don't understand yet. And, I get side tracked easily. It's hard to follow through with some of my trouble shooting and I don't have the tools I need so I'm always trying to adapt what I have on hand. I may just bite the bullet and take it to my local GM dealer.
Team Owner
Joined: Jul 2004
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From: Hartford WI
No. Honestly, I'm way out of my comfort zone. I have to stop and think hard about everything that's going on in this system and there's so much I don't understand yet. And, I get side tracked easily. It's hard to follow through with some of my trouble shooting and I don't have the tools I need so I'm always trying to adapt what I have on hand. I may just bite the bullet and take it to my local GM dealer.
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Instructor
Joined: Jan 2013
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From: Friendly WV
It's so easy, a caveman can do it. Find schraeder valve, unscrew cap, screw fuel pressure gauge on. Turn car to run and see pressure. Turn car off, go for a bit and see pressure. Run car, see pressure. Take off regulator hose and see pressure. Go for a WOT run and see pressure.
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From: Austin TX
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From: Hartford WI
My bad. $18 for an injector but $105 for a set of 8 which is $13.13 per.