SC400onDubz

Hey,

I am working on my 91 LS400.. I bought it not running. It looks like someone did a timing belt change on it recently, the water pump oring is leaking, so they must have really known what they were doing.

Anyway, I only runs on like 6 cylinders. I have replaced both coils twice, new wires, plugs and the left hand cam sensor. It is very wierd, two cylinders on the first side (left drivers) distributo cap are not firing. 1 and 5 are not firing but the other two on that same cap are firing fine. THe other Right hand side is totally fine. all of them are firing according to my sears plug spark tester. It sounds so much like a coil but I have replaced them and swapped them. still the same.

The timing belt is on correctly, I checked that first. Compression is very good 190 dead even all the way around. No check engine to help also. And if you put it in Drive it has no power at all will not pull it self in drive. even at full throttle.

Anyone with service manuals ??

THanks in advance

VVT-i

One of your coil pack may be bad. You have 2 coil packs, one by the ac compressor and another one by the thermostat housing. I've seen those goes bad and the car has no power( feel like cat. convertor clogged up).

sha4000

iTrader: (1)

if the coil were bad none of the plugs would be firing on that paryicular side. you might have to change the distrbutor cap and rotor plus all the plug wires. even without 2 plugs firing the car should still move which leads meto believethat you might have transmission problems. i had a tranny go out on my 91 due to improper maintenance and when it did my cae wouldnt go over 10 miles per hour no matter how much gas i gave it. check the tranny oil an smell if it i burnt and what color it it. hope its not the case b/c that is goona cost you at least 2k to get it rebuilt and 4k to get a new one. carsprobably not even worth that much. good luck and sorry

additude

If you have only 2 cylinders not firing then it is not coils or the cam sensor.

It's possible the dist. cap is bad.

And worse, the computer is bad. (It may have something to do with it, but I am not for sure).

It's also possible it's a mechanical problem. Blocked manifold intake, bad or clogged injector, etc.

With two cylinders not firing you are possibly pumping un-burned fuel into your cat converters and are going to clog them up. That will be a very-very expensive mistake. If you need to replace one of those cats it's going to cost you at least $1,000 so be careful.

Good Luck.

Wes

koolaidman

check for fuel

some1 told me this everytime per cylinder

suck
squeez
bang
blow

u obviously did the compression test so the only thing is bang

so check for spark and fuel.
for fuel move injector connector. if the problem moves u know its either the harness or the ecu
if it doesnt move. u know its the injector

btw who needs a sparkplug tester. pull the plug disconnect the injector and start her up with the plug grounded

sha4000

iTrader: (1)

if you want to check to see if the injectors are firing an easy way is to start the car take a long srewdriver on the top of ech injector an put your ear to the butt of the screwdriver and listen for a ticking sound which would let you know that each injector is pulsing on and off. this is afe to do so dont be worried. butlike i said you should change the cap,rotor,plugs and wire first to see if this will solve your problem

koolaidman

yes thats almost the correct way. what if u have carbon build up so only a little fuel sprays. u still hear that ticking sound. the only real way to do it is do a injector volume test. but i usually move the connector for the injector arround to find them

sha4000

iTrader: (1)

carbon will not build up inside the injector but inside the cylinder and the volume test will let you know if the injector itself is clogged from particles in the fuel that build up inside the injector. but this has nothing to do with the plugs not firing. the things that cause this is a bad ecu,wires, plugs,coils, ignition control module and if one of the sensors that work together to start the car is malfunctioning. since 2 plugs fire and 2 dont i would suspect the plugs or wires instead of the coil but since you have done this already change the distributor cap and rotor

koolaidman

ull be surprised that there is carbon build up near the tips of the injector. it comes from the emision system.

i agree it has nothing to do with the ignition system. but that could be a reason y its missing.

he also said he checked for spark. and that leans me more towards the fuel system.

especially when he said this
witch i know now it has to do something with the fuel system. ie partially clogged or cloged injectors or even bad injectors.

like i said earlier move the connectors arround for the injectors. if the problem moves its more than likly the ecu or bad harness
but if it doesnt move its the injectors

and he also said this
witch i know now it has to do something with the fuel system. ie partially clogged or cloged injectors or even bad injectors.

like i said earlier move the connectors arround for the injectors. if the problem moves its more than likly the ecu or bad harness
but if it doesnt move its the injectors

sha4000

iTrader: (1)

[QUOTE=SC400onDubz]Hey,



Anyway, I only runs on like 6 cylinders. I have replaced both coils twice, new wires, plugs and the left hand cam sensor. It is very wierd, two cylinders on the first side (left drivers) distributo cap are not firing. 1 and 5 are not firing but the other two on that same cap are firing fine. THe other Right hand side is totally fine. all of them are firing according to my sears plug spark tester. It sounds so much like a coil but I have replaced them and swapped them. still the same.

this is his whole statement, so all plugs are not firing. i know that the injectors are above the cylinder so theres always a chance of carbon build up on the outside of the injector but its unlikely unless that particular cylinder has bee runningrich for a long time. b4 i suspect the injector in a no fuel situation i would check for correct fuel pressure and if that wasnt ok i would suspect the fuel filter then the fuel pump in that order. so it could very well be a fuel problem along with the no spark problem but you can only check one thing at a time and then move on to the next issue. now if fuel pressure is good then you would move to the regulator and then onto the injectors. you have a point in what you say i would just go about figuring it out using a different procedure. lets us know the problem when you figure it out ok thats why i say change out the cap and rotor since you didnt say it was changed

koolaidman

1) he already said that he has spark in all cylinders
2) he said it wasnt running when he got it
4) if he had fuel pump or fuel filter problems all of the injectors will be acting up not just 2

like i said earlier.
its more than likly an injector problem not a fuel delevery or spark

sha4000

iTrader: (1)

[.

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this is not about who gives the best advice so would you just read his statement and tell me what it says. i know you said that you work in a shop but so do i and we both could still be wrong. even if the injector was partially clogged how would that stop the plug from firing?it seems likeyou are focusing too much on what im saying instead of reading his whole statement. since he replaced BOTH coils TWICE plus new plugs and wires and since all other cylinders are firing which means FUEL is flowing( i only mentioned filter,pumpm regulator,etc.. b/c theseare the things you check when you have a fuel problem) then you should check the circiut btw the coil and the sparkplug wire which is the distributor. you dont have to qoute me to prove your poiny b/c its not about me, its about helping him diagnose his problem. when he fixes it im sure hell get back to us and if you were right you can rest in the knowlegde that you helped a fellow member in a tight situation.

koolaidman

grr@ needin to be 10 char long

sha4000

iTrader: (1)

ok koolaide your the man

mickael

i have a 92 sc300 having similar problems, it drops the cylinders 4, 5, and 6. and runs rich. and it burned up all the plugs and wires. and the idle is off sometimes it idles so lw the engine stops, i had the motror replaced and a lot of other work done to it now i do not know how to fix, a mechanic tested it and said it is either the computer or wiring harness or distibutor but i have put a lot of new parts on it and i do not want to just keep on throwing money at it. if anyone can help me please tell me thank you