90 5spd CEL codes - no boost

decipha

Registered User
Car is a 90 5spd sc

I got codes (Key On Engine Off)
22 - MAP sensor out of range
67 - Improper signals from clutch switch?

I got these codes from the (Key On Engine Running)
42 - 02 sensor "rich"
33 - EGR valve position
77 - operator error during dynamic response portion of engine run self test
74 - brake on/off switch action not detected during dynamic response portion of engine run self test


alright let me clear this up...

my map connector is broken so its not connected, the harness is just resting there. 02 sensor is getting some weird readings because i have an exhaust leak. the egr was removed by the last owner. the last two codes were because i didn't lower the e-brake when the scanner beeped... my fault so forget codes 77 and 74 there usually not there i messed up this time :p

also, the car will not go into boost, as soon as it goes into boost on the boost gauge the car starts bucking, fuel pressure is 42psi with the engine off, and 38psi with the engine idling. As soon as the gauge goes past 50psi the car bucks, I can get the car to make 12psi of boost and 60psi of fuel pressure if i floor it but the car bucks really nasty and i have to let off the throttle so it won't stall.

also, i just noticed that while the scanner does the egr test the exhaust leak seems to go away for a couple seconds, then once the test is done the exhaust leak comes back. anyone know where the egr valve is located?
 
EGR Location

It's located behind the Inlet plenum look down, better to remove the passenger side cowl! Has a pipe from it at bottom going to exhaust!But you said it was removed so you might not see it.

Tom
 
i'll check it when the sun shines its best, thanks alot i got a feeling its still there just disconnected. wierd how the exhaust leak went away when the egr test started and came back a few seconds later when it was done the egr test. :confused: hermm
 
make sure its plugged in at the EGR sensor/relay deal in the back...its a little black box with a nipple and a harness connector. that rubber hose from the nipplegoes to the UFO looking deal coming from the manifold
 
i think your right, i got a feeling that if i change out my plugs and wires all will be well. i'll find out next week when i get some free time
 
Car is a 90 5spd sc


77 - operator error during dynamic response portion of engine run self test
74 - brake on/off switch action not detected during dynamic response portion of engine run self test

I think 77 means you didn't floor it enough when asked to.

I believe 74 means the BOO switch was not activated during the test. You have to step on the brake pedal at one point.
 
Plugs and wires are so fun on this car. Just pulling the wires off is better left of some with an obsessive-compulsive disorder. Buy a box of Band-Aids and we’ll see you in 4-5 hours.

But seriously, do the drivers side from the bottom, 20 minute job for me. Someone younger, maybe 15 minutes. The passenger side, besides removing my air intake tube, I also unbolt the A/C compressor and move it out of the way. Some assorted extensions and universals work well from the top for 1 and 2. 3 might be better done from the bottom as well. I've used a long piece of air hose to get them started on the passenger side. Coat the threads with anti-size. Don't forget the order of the coil isn't in order.
 

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nope....

took me less then 30 mins to do the spark plugs on this car, everythings removed ac etc so u can just reach down np did the sparkplugs 2 xmas's ago plugs should look good, i changed them thinking that was the problem...try re gapping them bc i never gapped them ....
 
I changed the plugs and wires.

had some carquest wires that didn't look that old and autolite app2455 plugs that were black but in good shape.

plugs were gapped dead on except for 2 of them was at .057
one of the plugs was really loose I removed it using my hand.

new plugs and wires, autolite 103s and now the car seems to run better.

I took it on the interstate and got it into boost :)

at about 4k in 3rd gear and 10psi according to my vac gauge the car backfired loud as f***. I backed off throttle and went back in boost this time I stayed at about ~8psi.

Car seemed to run alot better but it still bucked and backfired. Any ideas?

Also, I'm thinking the exhaust leak is whats causing my boost problems.
anybody think thats possible? I got a feeling once I weld up the exhaust good all my boost problems will go away.
 
im completely redoing the exhaust tomorrow because i finally have a day off work and i just got my bottles refilled :)

I'll post back tomorrow to let you know how it runs, if that doesn't solve the problem im going to change out the injectors.

if that doesn't solve the problem im going to pull the front cover and check the timing, maybe the cam jumped a tooth?
 
i just checked the fuel pressure

i primed the pump and got the pressure up to 40psi

let the car sit 1 1/2 hours and now the pressure dropped to 11psi


is this normal or do i have a fuel leak?
 
Fuel pressure dropping to 11 psi is probably normal. I just checked mine after 15 min and it's down to 35 from about 45. One of those plug wires might be bad causing it to buck but the backfire doesn't sound like a plug wire. When mine backfired it was from dead O2 sensors causing it to run really rich. Check them and see if one has carboned up more than the other.
 
i removed my passenger side o2 and WOW! my car runs alot better.

doesn't stall anymore, nor does it have a crappy idle.
car seems like its new again. I still can't go into boost but i got a feeling once i replace the o2s and bring my fuel pressure back up it'll run great.

wish me luck
 
another problem!

i was driving the car on the interstate, i came to a stop and the car died, tach dropped off and it stalled. (first time that ever happen)

i tried to start the car and it wouldn't, didn't start until the 3rd try.

I'm thinking maybe the crank sensor or cam sensor is faulty?

but from what i thought, the cam sensor is only used to start the car right? I thought if the cam sensor goes out while the car is running you loose tach but it stays running?

any thoughts?
 
Starting on the 3rd try sounds like cam sensor but it could be just a coincidence and it's something else. I have had the cam sensor cause mine to stall but it would start misfiring 1st and always restart by the 3rd try. When my crank sensor/balancer failed it just suddenly died and would restart but only after many, many tries and then ran fine until it quit for good a week later. Everytime my crank sensor has failed the cam sensor failed a week later. I'd just replace them both and be done with it.
 
cam sensor completely failed on me 3 days ago.. i disconnect it and now the car runs perfect... hits boost, no idle problems, no surging, no bucking, and pegs 11psi of boost at WOT.

car is now fixed and is running great... runs like an engine with only 40k should run.
 
i jumped the gun, car was giving me problems still, i disconnected the belt and the car ran perfect. Put the belt back on and it wouldn't even start :confused:

i thought the cam sensor was faulty but since it ran perfect with the belt off i knew it had to be good. I then decided to pull the harmonic balancer off to get it rebuild, when i went to go take it off i found that the bolt on the crank shaft was broken :eek:

that explains why the car ran perfectly fine with the belt off but wouldn't even start with it on. But now I had a bigger problem since I have to figure out how to remove that broken bolt from inside the crank.

hopefully the P.O.S. bolt that isin't suppose to be there anywho is weak enuff that i can chip it away with a pick. The damn balancer had 7 washers holding it on. :(
 
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