MVetter

**8/29 edit- New information found. Basically disregard all this and find the newer post down the page.**

Hi there. I found this forum via a Google search. I thought it would be in my best interest to learn more about this problem and my potential options before my mechanic takes a stab at it.

I am not a mechanic. I can change the oil if necessary and point to various things like the fan and say "That's a fan". I've got an '82 that started having issues yesterday. My mechanic, as I originally described the symptoms to him over the phone, thought it might have been the fuel pump. When he took a look at it he told me one of the injectors died and wasn't doing anything, therefore I was running on half an engine. He hasn't worked on a crossfire injection in ~15-20 years, so I know he's not looking forward to this. He told me I'd probably have to buy 2 injectors for synchronization purposes. The one that's working currently is just so old that it might have a lower flow rate than the replacement part and blah blah blah I should get 2 so they match.

He's hinted this will be 'difficult' to work on, but thankfully less painful than the fuel pump which is, according to him, "like getting kicked in the *****". I just am trying to find out what my options are. I'm in central Illinois which is a pretty big Corvette area. I thought maybe someone has a friend of a friend that knows someone that has devoted their life to 1982 crossfire fuel injectors and can help. I do trust my mechanic, and I don't want to bash him in any way, I just feel I should know more.

My replacement parts catalog lists injectors at $130 apiece. Anyone familiar enough with this entire process have know what I should prepare myself for? Any response is appreciated. Thanks.

0grandmastercorvette

How many miles on your engine?

Was the car running fine (good idle and acceleration) BEFORE this issue? If not you may have other issues, such as vacuum leaks.

I have worked on a few in my day and they are a bit touchy IF you do not have good throttle bodies. If the throttle shafts are loose and "have a mind of their own" when you go to apply pressure to them to make them open. Then trying to balance these throttle bodies will be darn near impossible. The brackets that are staked to the throttle shafts MUST be tight. NO WIGGLE in the staked on bracket(s). This wiggle will make the balancing of them a constant varing issue. FROM PERSONAL EXPERIENCE.

I use the balancing method that GM states in the service manual. I use the manometer and perform the balancing just like it is written and when it is performed correctly, the car will launch very well without any hesitation or bogging. This also depends on other internal issues that I won't get into right now.

I have tried to use the "other" balancing method out there, but I like using the manometer because it is very precise. The "paper" method is ...well just say... I don't like it at all. Not a precise method and requires a bit of fussing with to get it right, and seeing how I have the tools to do it like the "book" states, why not do it that way. I am not a hobbyist and don't have time for doing things that do-it-yourselfers can try to do in their own garage. MY time is money...

You may need to have your throttle bodies sent out for re-bushing the throttle shafts or even upgrade to a larger throttle plate diameter for better performance. Just make sure that the company you choose DOES NOT do away with the PORTED VACUUM connection that is required for the factory adjustment procedure to take place. I have installed some that do away with this port and it is a @#$%^&* to get right. Alot more time to get things adjusted because I can not use my manometer.....UNLESS I drill out the ported vacuum port again because they plugged it off. Either way ...in my opinion...some BOZO has to always try to re-invent the wheel because THEY think THEY can make it better, and even write stating that THEIR way is JUST AS GOOD, if not BETTER. I totally disagree with them because I'M the one installing these parts and trying to make it work like I know it should. So basically, be cautious and ask questions, or you/your mechanic may find out the HARD WAY. Incresing the throttle plate size is a GOOD thing if you choose to do it. It really does help...Alot.

GOOD LUCK AND WELCOME TO THE FORUM.
"DUB"

daleman

Im assuming he checked the electrical connections.
I've replaced the fuel pump in my 82 and my ***** are still in tact.

MVetter

I think around 60k miles on the engine, maybe less. The ONLY thing different I noticed happened a week ago. Upon starting the car either hot or cold, it required a little throttle and would not idle until a good 15 seconds or so had passed. Acceleration may have been a little sluggish but that may be in my head. To my knowledge that's the only thing weird/different I noticed.

Also I have no idea what you're talking about in regards to throttle bodies, but I appreciate the response. I'll make sure my mechanic gets the information so perhaps he can make sense of it because it is entirely Greek to me.

Nothing has been checked as of yet. My mechanic is one of those, "Well I'll try to get to it soon but I got these 10 other cars ahead of you. I'll let you know" kinds of people- busy.

7T1vette

Check on the internet for sources of rebuilt throttle bodies (there are two of them under your air intake housing). You might be better off just exchanging yours for new rebuilds which have been set up properly. Then you can just have your mechanic install them [at some enormously over-inflated installation charge ].

I don't know if you can damage the engine by running on just one throttle body.

terry82

you need this page http://www.crossfireinjection.net/

fadingrockstar

2K14C7

I agree. I changed the fuel pump on my 82 several weeks ago and it was actually quite simple.

I assume your mechanic knows that for 82 the fuel pump is in the gas tank and is removed through the fuel filler door. You don't have to drop the tank.

If I were you I'd change the pump as it is a very common source of problems. There is a 3" rubber hose that connects the pump to the fuel line that WILL go bad at some point. Mine was split and caused missing, surging, erractic idle, stalling, hard starts and other problems. After the new pump was installed it ran like new.

Good luck.

MVetter

Oh dear. No, he did NOT know that. The last thing you want is your confidence shaken in your mechanic. I don't suppose there's some listing of trusted/reliable Corvette mechanics by region is there?

To the rest of you, thank you for the handy links. Looks like I have some reading to do.

edit- I'm having a hard time tracking down rebuilt throttle bodies for sale. Is there some particularly good area I should be searching? All Google yielded were things like the following:
http://cgi.ebay.com/ebaymotors/Cross...71410002r35107
http://cgi.ebay.com/ebaymotors/New-G...71410003r16362
http://www.zip-corvette.com/Zip/prod...CB9FD8FCD9DB64
http://www.corvettepartsman.com/inde...OD&ProdID=5755

Those mostly seem to be rebuild kits, not actual rebuilt throttle bodies.

7T1vette

The first site you listed looks interesting. Increased bore injectors will work fine on your setup "as is"; if you put a stronger cam in, those injectors will really jump the power. Send a request to the Seller to ask if the injectors have been properly balanced and adjusted. If so, that sounds like a decent deal.

The second listing is for later model engines, so I don't know if those are direct fit/use for your engine. Could be...could be not.

Even if you replace the injectors, you may still be wise to replace the pump while you are at it. Lots of years of use....you make the call.

Dirtbuster1

Have you checked the fuses in the fuse box by chance? There are 2 fuses located in the top of the box. You could also switch your fuel injector wires to verify it is a bad injector. You can get the injectors rebuilt pretty cheap. I believe most parts stores carry a injector test light to verify that the wiring is working properly.

MVetter

That's all well and good but right now my primary focus is fixing, not upgrading. Money is tight this month and I'm planning on selling a few possessions to be able to afford the repairs. I don't know if there's anything wrong with the throttle bodies; it might be just bad wiring that crapped out. I was on the interstate when the problem first manifested; I don't know.


I have not checked the fuse box. However while we're on the subject since someone mentioned earlier the fuel pump is easily accessed through the top of the car, maybe there's an easier way to get to the fuse box as well. Last time I had to get at the thing it was one of the most uncomfortable/awkward experiences ever. I think I had one arm cocked behind my head trying to hold a flashlight, my head was at an angle that shouldn't be possible, and my other arm was... somewhere. It was awful. Is there some easy trick to this as well?

Dirtbuster1

There is no easy way to those 2 fuses. The best you could do is to remove the AC duct for better access. Take a Voltmeter and compare the voltage on each injector connection. Turn the key on and check voltage while trying to crank the engine. I doubt you will get any voltage with just the switch on. The test light only cost ten dollars.

The Fuel pump should not take anyone more than 2 hours out, and 2 hours in. Worst case, unless you wire it up wrong.

0grandmastercorvette

MVetter,
If you carefully read my earlier post I wrote on where to check your throttle bodies where problems in the staked on brackets to the throttle shafts wqhere yoour accelerator linkage connects to the throttle bodies can have free-play or "wiggle in them. This can cause for issues with the balancing in the two throttle bodies.

The fuel pump can be an issue, and like mentioned gets serviced CAREFULLY through the fuel door opening.

Next thing... IF you get throttle bodies...read my earlier post and MAKE SURE you ask the questions that I mentioned. There is no way that the throttle body rebuilder can balance them so they are just "simply bolt on" and perfect. They can be adjusted using the ...like I mentioned in my earlier post...using the paper method. But the paper method is not as good as the manometer method. Have used both methods and the manometer is MUCH MORE PRECISE.

To check your injector pulse, your mechanic should have an assortrment of "noid lights" which plug into your injector wiring and when the ignition is turned to crank, the "noid lights" will pulse and he can determine instantly if you have bad wiring or even a bad computer.

At 60K miles I would bet my mothers eyes that the gaskets under the throttle bodies and the gasket under the top intake mounting plate, (the plate that your throttle bodies are bolted to) is hard, brittle and possible leaking vacuum. If your mechanic has a smoke machine for finding vacuum leaks, he can find it very quickly. I have worked on many and when the intake top plate is removed it has shown damaged gasket material and it is so hard that you can easily snap it in two.

Possibly acquiring a FACTORY service manual would be much help now and in the future.

If you need to talk to me about this I will be back at work on Tuesday. CAll me..its your choice. You are dealing with an area that care and attention to detail must be observed and if your mechanic does not give you the vibe that he wants to do it correctly, find someone else because you may be getting yourself into more financial issues than you want at this point.

I do this for a living and I have paid my dues in making sure procedures are followed becacuse I do not have time to explain myself AGAIN because my customer ONLY wants me to DO WHAT HE WANTS and does not listen to the voice of experience, and when the job is completed. The other issues that I had mentioned that needed to be checked outor replaced, were dismissed as a waste of time and money for him/her. Eventhough they were there to see the results of the vacuum leak test. Then I have to go back in a second time and replace parts because the car will not run as it should.

It is your choice... whatever you decide...and I do not have a crystal ball and can not tell what is wrong. but I do know enough to try to advise you from my past experiences, regardless what has worked for others on the forum. Each car is different. Sometimes it is a simple fix, such as a cut wire, plugged fuel filter, bad IAC valves or even a sticky or slightly open EGR valve. But if only ONE injector is squirting fuel, this is an issue that really needs a mechanic who is willing to FOCUS on the problem and not be rushed because they haven't done this before and has a bunch of other cars that are waiting to be serviced and you get the "band-aid" fix.

"DUB"

Kipring

Coming from a guy that just bought his first toy and is a network admin by trade, as long as your careful, document your work (pictures!), and get assembly information on the car you can do a TB rebuild. But this is assuming your willing to take a leap of faith that you can do this and want to get your hands dirty.

My 82 was having surging issues at idle. I rebuilt them both over a weekend spending extra time and care to take pictures along the way and cleaning and inspecting every piece (I can do a writeup as best I can and post it). The gaskets were falling apart and the previous rebuild was poorly done. The rebuild was straight forward and good experience.

I completely understand the budget problems, I think everyone can relate; which is why alot of us have to become some what proficient with maintaining these cars. I love cars and working with my hands after spending all day behind a screen the vette is a great outlet for me (though I've only had her for two weeks so it is still in the love/star struck stage of the relationship).

I installed the TB this past weekend and the car is running strong with the surging gone!


~ Kip

Edit:

It is real easy to see the injectors squirting. Take off the air cleaner housing and crank her up. Sure you cannot get an accurate measurement just by looking but you would be able to see a serious problem (one injector not squirting or barely squirting).

Check the linkage, plenty of documentation floating around on checking it, like Dub suggests. I was lucky and it seems like mine is in good order.

MVetter

Bumping this thread because I finally have had more time to work on this and diagnose the problem further.

It is *not* the injector. I thought it might be a wiring issue so I've been using a voltmeter to test the wires running from the injector to the wiring harness (checks out fine), wiring harness to the fuse box (checks out fine), fuse box to the ECM (oh hell, I need a wiring schematic). Basically I think I've narrowed it down to something wrong with the connection. My best guess is the ECM went haywire and I need a new one. I can't test the wires from the fuse box --> ECM because I just don't know which is which right now. I don't suppose any shops around here have service manuals specific to the '82, so I'll probably need to track down a GM service manual and wait for that to be shipped in.

Pity, too. Today is a perfect day for drinking beer and working on engines.

jdp6000

Here is something for you to try. Switch the wires on the injectors and see if the one not working works or if both suddenly work. Which is it by the way.?I'm going to guess passenger side.

I assume you have checked the two fuses...one for each injector?

It sounds to me like you have a weak pump. The pump sends fuel to the throttlebody on the driverside. The driverside throttlebody has a regulator built into it. If you are not getting 9-13 psi one or both of the injectors may not work.

There is a shop manual for the 82. You can buy them on ebay. Make sure you get the 1982 Corvette Shop manual. Its a red cover.

Jim

jdp6000

One more thing. if you think its wiring. Follow the wires around to the black box on the passengerside firewall. Open the box up. Plenty of big connectors in there. I did have corrosion in one of them.

Jim

MVetter

Yeah, I switched the wires and found the injector itself was perfectly fine. The injector in question is indeed the passenger side. I will take your advice and have a look at the passenger side box and check for corrosion as that seems very very likely.

As far as the pump goes, what pump are we talking about here? Fuel pump? If this were the case would I be able to test this by say, disabling the driver's side injector and forcing everything through the passenger side? Or would it not work that way.

Out of curiosity what leads you to suspect the fuel pump?

edit- that whole thing about the fuel pump doesn't make sense. If it were the fuel pump why would the wiring connected to the right injector not then work if plugged into the left injector? If I unplug the left injector, the right one doesn't work. However if I put the driver's side wiring on the passenger side's injector, the passenger's side injector works. No, this leads me to believe it cannot be the pump. Something in the wiring is pooched. I think it's between the fuse box and the ECM. Is this a known area for wires to get pinched/grounded?


Unrelated broken part- My AC slider, the sliding lever where I turn AC on high/low/vent, has been sort of funky ever since I purchased this car from the previous owner. It didn't slide correctly, like something was stuck in it. I finally found out why, but I don't know what to call the part. The slider attaches to this wheel with an arm on it. The wheel has a metal spacer that looks sort of cog-like and is bent meant to give tension. Holding all that together is a small white round piece of plastic with two prongs that snap in and hold it all in place. One of the prongs is broken. What is that thing called so that I might order a new one?

MVetter

Well,
It took a lot of beer and hard thinking, but the culprit is the ECM. Who'd have thought. Ordering a new one on Monday. Thankfully they're only $150.
For those curious on how I arrived at this diagnosis, I unbolted the ECM from its mounting brackets so I had (a little, very little) space to move it and shove some jumpers down in there. I jumped the functional and nonfunctional injector wires and bam, two functioning injectors upon ignition.