OK, so I got into my car to come home from a meeting yesterday and out of nowhere my max (93 GXE) was absolutely running like crap, sputtering, missing and no power at all. It reminded me very much of how it ran last summer when I had a bad coolant head temp sensor. So, I get home and start tinkering with it today checking for codes in the ECU all I get is a 33 (o2 sensor) and thats it. I do the basic tests, with car running remove plug wires and listen for a change to how it runs and the good sound of spark. I get to the front middle cylinder and it makes no difference if the plug wire is attached or not so I get to looking a little deeper and notice that every one of my injector plugs are missing the spring clip thats supposed to hold them in place, so one by one with the car running I use a needle nose pliers and pull them off one by one checking for any change in how the engine runs, all make a dramatic difference except the same middle front that had no change from removing the spark plug wire. I'm assuming this means that injector has failed? Secondly why would all the clips on the connectors be missing? Ya think someone tested em before and was just too lazy to put them back on? The plugs are fairly corroded is there anywhere I can get replacements for them or even better is it possible to get a whole new wiring harness? Mine is all very dried out and brittle (was a TX car until a year ago) Anyhow, if someone knows the resistance these injectors are supposed to have or any other good advice please let me know. I'm off to find my multimeter :-)

thanks in advance

 

IIRC resistance should be anywhere between 10-14 ohms. It definately sounds like your injector is dead.

I had the same issue with the g/f's maxima after replacing the bad injector and it was just the POS spark plug wire from Advance Auto, make sure your wire is good before doing all that work. good luck

 

Anyone have any ideas about the connectors or where to find a new harness etc?

 

http://www.fiveomotorsport.com/Injector_CONNECT.asp
Take a look at this place and see if your connector is there.

 

Thar she blows!!

 

Eh, so I tested the injectors. Ohm reading anywhere from 22 to 80 so thats just great. Priced a set online with all new connectors for 500 bucks, hope I can find a better deal somewhere. Cars running like crap and my mileage sucks.. I almost feel bad about driving it when its running so poorly. Anyone have a set of VG injectors laying around that you want to get rid of to a good home? :-)

 

I got code 33 on my ECU and it is running pretty crappy. Can you tell me what the symptoms were when you had the bad coolant head temp sensor? Was it the sensor or the wires?

 

Which engine do you have? VG30E or VE30DE?

 

It is a 91 VG. I just replaced injectors, plugs, air filter, PCV, some vacuum lines. After finishing the work I had it running in the driveway and it got hot but I drove it and it cooled down and was doing ok Not perfect but not that rough. The next time I started it I got a small amount of white smoke and it was running real rough and reeked of gasoline. One of the plugs I put in was gapped wrong and was wet with gas when I pulled it back out and regapped. It got smoother after that and further checking shows a dry plug, but it is still too rough to be good and still smells strongly of gas in the exhaust. Slightly better than before adjusting the plug.

Now when I start it, it is still running rough but I'm getting no white smoke. It doesn't have much power when accelerating but it will get up to speed eventually. I have no oil in the radiator or water in the oil so I am hoping the headgasket is ok.

The only code I've seen so far is 33. Also I found the vacuum line to the fuel pressure regulator to be questionable.

 

Sounds to me like fuel is leaking past the injector o'rings causing a severe rich running condition...Did you replace the injectors yourself?

 

i suppose that's possible.

 

I wouldn't trust old recycled injectors because they were pulled out probably because the person had one or a couple going bad. you get a 100K + miles out of them and they go bad. I don't advise messing with used ones - or rebuilt ones either. I've read too many posts about the rebuilds failing after 6 months.

I order mine through internetautomart.com and he includes the 2 o-rings with it. When you change the injectors, take the time to replace all the vacuum lines and fuel hoses that are under the plentum.

 

Sorry. have been away for a few days. As for the coolant temp head sensor, it ran like crap, barely idled and was very much like mine is runnning now. One tell tale sign is your radiator fans running non stop or not at all.

 

Is it a good idea to just replace that while you have access to the fuel rail?
Its another $80-100; I don't know if these tend to last the lifetime or not...
Thanks
DC

 

I didn't replace mine and no one seems to recommend it like they do the hoses.

 

haven't seen a 3rd gen with a bad fpr that I recall.

 

I suspect when I set up my rails to an air pressure test rig (to test my injectors for fuel leaks), I may have damaged the fuel pressure regulator.

Ever since doing that, the car takes longer to start after it's been sitting. The longer it's been sitting, the more drastic the effect. I have to wait for the fuel pump to run before starting if it's been sitting for very long, or it will jsut crank and crank. It used to start up SO quickly.

There are no smells or visible signs of any fuel leaks external to the engine, and the engine drives almost perfectly now, I get full engine braking deceletation, which indicates the injectors lower o-rings aren't leaking either.

So I suspect the fuel pressure regulator valve is just not completely sealing, when the engine is turned off and sitting, and allows the fuel pressure to bleed off.

I have a spare fuel pressure regulator (on another set of rails) that I believe is good. I hope I can replace it without having to take off the plenum & upper intake, like for the injectors. After replacing it, i will report back as to whether it fixes the starting problem.

 

Just to follow up on my earlier post -

I was able to replace the fuel pressure regulator in my VG without too much effort. I removed the MAF and the large plastic air intake tube, and from that area was able to reach the fuel pressure regulator screws with a long phillips screwdriver.

The replacement fuel pressure regulator did the trick in fixing the slow starting woes! My car is starting immediately now! Jump in, put keys in and it just starts.

Just to reiterate, my old fuel pressure regulator did not fail from normal use. I think I damaged it when I hooked up compressed air to my fuel rail to test the injectors. I capped the outlet of the fuel pressure regulator during the test to make sure it would not leak, but maybe that caused backpressure through the fuel pressure regulator and was not a good idea. Or, maybe I just used too much air pressure.

I also tuned up the ignition system - all new plugs, and cleaned deposits found on inside of the cap, and man with those changes, and the fresh rebuilt injectors and freshened injector connectors, is the max running good now.

 

for now....

 

+1

just so you know, jake..... there is no way to rebuild injectors for our cars. they just clean them and rebox them. and since our injectors fail electrically rather than by clogging 90% of the time.......

 

I am aware guys that "rebuilt" injectors are just used ones that are cleaned up, tested good, and in my case, a set of six matching ones. And that's what I chose on purpose for my 216k mile, 1989 beater max.

I tried making a set of six "python" new ones work on two occasions before FINALLY sending all of them back, but they were always nothing but trouble and were manufactured much more poorly than the OEM JECS injectors were. The pintles wouldn't shut, leaking gas into the motor. The upper o-ring groove was too wide, causing leaks. Poor design and/or quality control!

So I am quite happy to have the OEM JECS/Bosch ones back on there, even if they do have some miles on them. Although I got three+ years out of my last used set, I also have a theory about what might be making them fail early. And if so, I've addressed it and my next set won't fail. I found a lot of corrosion built up in the connectors to my injectors, which was not reliably conducting and also the engine vibrations might have been making the injectors fire multiple times rather than a single time per "pulse." If this was happening, it would have caused the coils to overheat and fail as a result. It may not be simply that fact that they have "high miles" on them, which causes them to fail. It might be the bad electrical connection that causes them to fail.

I've addressed the issue with corrosion in my connectors, by taking the connectors out of their sockets, cleaning out all the corrosion, applying dielectric grease, and re-tightening the connectors so they "pinch" well again on the injector terminal. I have confidence there is a solid electrical contact once again.

If my theory about the bad connections causing the injector failures is right, I should get some nice, long life out of my current set of good used OEM ones. Also, it would be a waste to spend money on brand new ones without addressing the electrical connection issues, because if my theory is correct, they new ones could fail in short amount of time.

I would like to disassemble one of the injectors that failed and see what I can learn about how the electric coil failed. I'm curious if anyone else has taken one apart?

 

I just replaced a bad injector in the same location. Put everything back together and it ran like a raped ape for a day. Went to a party, woke up the next morning and it ran like crap, but not as bad as before the repair.

Started hard, idle was rough with gas smell. Ran fine under acceleration.

Any ideas fellas?

 

^^^hmm so you replaced it then it ran fine. the next mroning idle rough with gas smell.

sounds like either your missing an injector ring or it's the ring is ripped and it's leaking.
i had this prblem before when i replaced my injectors i did'nt put a ring in it and i got a code; leaky injector.

 

I would check other injectors. These tend to fail VERY close in time to each other. I had one replaced and literally had another fail within 3 days.

 

can anyone post sources and prices for injectors?

 

Go to that five-o site, best prices you will find.

 

Yo Hectic, I'm really happy for you, and I'mma let you finish. But Internetautomar's site has some of the best prices of all time. Best prices of ALL TIME!

 

All other cylinders are firing fine. It's to the point where when I pull the plug wire on #4 cylinder, there is no change to the rough idle/running condition. Tested the resistance of the "new" injector and it reads 14 ohms. Ok there I presume.

A few questions, would a leaky injector, i.e. one with a cut/missing o-ring, cause rough running at low rpm? Also, why no change when pulling the plug wire? I have spark at that cylinder.

 

Of all the crap on the internet using that, this one the the best.