3-sge Jumping when steady speeding.

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EspenD
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3-sge Jumping when steady speeding.

Post by EspenD » 23/02/17 21:08

Hello! sorry if this has been asked before but i did´nt find any topics about it..

Its an 3-sge 92 mod.

My main problem is that as i wrote in the subject the car is jumping very much when steady speeding. It can feels exactly like im jerking the throttle pedal. and it does´nt stop before i let go of the throttle or push it further in, starting to accelerate more. when accelerating it feels fine, no powerloss or jumping. Also when i let go of the throttle it stops jumping.
Another problem that i have is that its idling badly. But its probably not the same problem.

I took the diagnostic test and i got 4 fault codes;

12 PRM signal: distributor/distributor circuit/starter signal circuit/ECU
21 Oxygen sensor signal: oxygen sensor circuit/oxygen sensor/ECU
31 Vacuum sensor signal: vaccum sensor/vacuum sensor circuit/ECU
41 throttle position sensor: throttle position sensor/throttle position sensor cirtuit/ECU Sensor "ohmed" OK.

2 months ago i changed the head gasket because of too much oil consumtion. at that time it was idling very high-1800rpms. after the head gasket change it kept idling high so i could not adjust the timing with a timing light. 1 month ago it atually fixed itself. it started idling at 1100rpms and i could adjust the rest with the idle screw on the throttle house. At this point i heard that it was misfiring( i could not hear this when it was idling at 1800rpms.) so i still cant adjust the timing properly... what is a bit strange is that when i try to adjust the ignition by ear. i have to turn the distributor as far to the right as possible..

*i cleaned the spark plugs and let the engine run for 15 minutes. It was already covered in black carbon dust after this. Running on too much fuel maybe?
I´m gonna buy new plugs asap but i dont think this is my problem...?

what diagnostic code is connected to the jumping when steady speeding?

Thanks!, -Espen

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abovetherim
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Re: 3-sge Jumping when steady speeding.

Post by abovetherim » 23/02/17 23:22

First thing to check is the static timing is correct at 0 deg TDC
see below here the white mark i have added to the notch on the crank pulley is at 0 deg
Image

Then check the pulleys are correctly lined up by either the marks on top of the cams as below
Image

or the pulleys timing mark lines up with the marks on the back plate. You can see in the photo below the dimple on the pulley and the ridge on the backing plate
Image.

If the timing checks out then next on the list is to check the ecu temp sensor (assuming no air locks). If this is misreading as cold the engine will over fuel once warm. To test meter it cold and plot a graph as it warms up. Should be an inverse curve starting at about 5kohms cold and 0.4 kohms at normal running temp
Vac leaks can cause overfueling.
Oxygen sensor can cause over fuelling.
High idle could be down to the speedo cable being too tight or the idle control valve being gummed up.

Have you got the BGB?? If not google it for a download or search on here for links. Wealth of info in it, including diagnosis procedures and testing info.
1991 rev 1 T Bar n/a 3sge import. A work in progress!!!

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pbmr2
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Re: 3-sge Jumping when steady speeding.

Post by pbmr2 » 24/02/17 7:41

High idle issue is prob an air leak, which could be something to do with code 31.
Any of the other 3 codes could be causing the issue, all 3 together and an air leak must be a nightmare of the ecu to work out the fueling.

Did you set the timing with the pins in the diag port bridged?

The TPS could have been disturbed while being checked out, causing a 2nd issue of an air leak. But there are lots of air leak possible causes.

get the BGB out and test the sensors as per the manual. once they are all working then hunt the air leak.
"Stop buying parts to solve the problem, findout what's wrong first!"

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abovetherim
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Re: 3-sge Jumping when steady speeding.

Post by abovetherim » 24/02/17 18:05

Yes I was going to mention setting up the tps as per the manual but forgot.
1991 rev 1 T Bar n/a 3sge import. A work in progress!!!

EspenD
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Re: 3-sge Jumping when steady speeding.

Post by EspenD » 16/03/17 23:06

Hello! And thank you for the feedback!

I finally had time to check for faults..



Here is what i did;

code nr 12: PRM-signal:
checked the wiring diagram for the ignition system. there is one wire from the igniter to the tachometer which is in bad shape. The tachometer has not been working on 3 different occations. for about 10 minutes, and then its back again. So i think this is the fault of this code...

Code nr 41-Throttle position sensor:
Ohmed the sensor OK. adjusted the sensor. checked wires from sensor to ECU for shortage and continuity.
checked voltage from IDL and E2. 11v. I also checked the voltage on the ECU on the different throttle positions. Everything seems ok with this, right?

Code nr 21- Oxygen sensor:
Checked voltage between VF and E-1. just 0-06v... this has to be a fault right,? the next boxes in the manual tell me to check the ground on the ECU for the oxygen sensor, these are ok. So according to the manual the ecu should be replaced..

To check the oxygensensor i needed to warm the engine up, i was low on fuel so i took a drive to the petrol station to fill it up. Before i drove i disconnected the battery so the fault code would reset.
After i filled it up i experienced a powerloss...(if i think about it, this powerloss was probalby there from my garage to the petrol station as well...) anyways, i drive 2 km and the car stops in a hill. Engine wont start again, i try and crank it too much so the battery is almost completely dead--> so the error codes would again be reset...i had to tow the car home..
the next day i start to cranking the car for 30 seconds, its coughing a bit and some fuel is ignitied, but not starting. it will help if i push the throttle all the way in.
I remove the sparkplugs and notice that they are very wet, so there is plenty of fuel, but they are also a bit oily...?? the engine has not jused any oil since the head gasked change...maybe this is just too much parly burned fuel? at least i hope...
Next i clean the spark plugs, and crank the engine with the spark plugs out and touching ground, they all give good spark.
I fasten the plugs again and it starts almost imedeatly. Bad idling like before...But i do notice a differense when i give it som gas in neutral...
I let the engine run for 10 minutes and go for a 500m drive. Still powerloss like yesterday and also shaking when idle speeding...runs rough. When i get back to the garage (stopping and idling) the engine dies out. start it up again and let it run for some more minutes.
I now try to do the diagnostics but now i get no codes! just repeatly flashing.
i go for another 500m run, now a bit higher speed, when i get back this time the engine dies out once more. But now i have to hold the throttle to keep it from stopping..

Maybe this is the time to try to adjust the timing with the timing light once more?
BTW whan can be the reason i could´nt adjust the timing properly before, its a bit strange to me that when i rotate the distributor all the way to the right its idling better.

I´m going to continue checking the oxygen sensor and so on tomorrow, but a little tip would be nice here, im pretty lost !

With all respect abovetherim, i don´t think this is the static timing, i feel pretty confident i got this right. I checked it before finishing when i did the head gasket, when i started it up it was "idling" smootly at 1800, plus it (at least before just now) had no powerloss.

Thanks a lot for taking your time and reading all this ! :)

best regards, Espen

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Re: 3-sge Jumping when steady speeding.

Post by pbmr2 » 17/03/17 8:18

Looking at the timing pictures above, the exhaut cam is reatarded. So for my mind, the belt timing needs to be looked at closer again.

When you set the timing did you bridge the pins in the diagnostic port? If not then the car corrects the change in timing.

The plugs don't sound too good, maybe change them. Got any pictures?
Have you checked the dizzy cap and rotor for wear and the leads for resistance?
Also your description of how the timing was set sounds like it may be setup to in a way that could be masking an issue.
Maybe the idle valve or mechanical timing or a vacuum issue or a mix of these?

O2 sensor, think this needs looking at more from your results.

Just had a thought, you say you replaced the head hasket so the head would have been off the car. Were all the vacuum hoses connected back up to the correct ports?
Also starting to think that the ISCV is sticking or underperforming, they get gunked up with oil and can stick, this means idle control is poor and can let in air during normal running. Carb cleaner has worked wonders for a number of people. They also crack which can been seen on close inspection. If you disturb it then new gaskets should be used.

Maybe something left feild like the actuators for the tvis/acis. the diaphram splits and becomes an air leak.

Test the ecu temp sensor, details in the BGB again. They often fail slowly so don't produce a code till they are fully dead.

Might be worth taking the lid off the ECU and just checking none of the capacitors have poped. bulging caps on them is a sign or leaking fluid from them. that or a full on burst out.

Good luck!
"Stop buying parts to solve the problem, findout what's wrong first!"

"Time is the true wealth, spend it well."

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jimi
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Re: 3-sge Jumping when steady speeding.

Post by jimi » 17/03/17 12:17

pbmr2 wrote: When you set the timing did you bridge the pins in the diagnostic port? If not then the car corrects the change in timing.
This is extremely important, you'll never get the timing correct if you don't link TE1 & E1 first
This article in KY2 on checking your timing may help CLICKY
Black is not a colour ! .... Its the absence of colour
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EspenD
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Re: 3-sge Jumping when steady speeding.

Post by EspenD » 19/03/17 17:10

Thank you once again for your feedback.!

Quote"Looking at the timing pictures above, the exhaut cam is reatarded. So for my mind, the belt timing needs to be looked at closer again." These pictures are not from my car :)

When i tried to use the timing light i did bridge TE1 and E1. But i dont think i got a connection because i cant remember to see the check engine light being on.
So with this in mind i first removed the dizzy and checked the air gaps on the pickups, rotor and ohmed the sensor connector, all OK. I also fixed the bad wires to the dizzy plug.
when having the plug out i checked the wires from the plug to the ECU. the NE on the plug is probably ground so i got a signal to about 10 different wires on the ECU. But the G-1 and G-2 was mixed compared to the BGB.I dont remember what was on the G- but this one was wrong compared to the BGB. im sure i got the cables right when i fixed it.
Anyways i cleaned the sparkplugs once more and started the car with the TE1 and E1 bridged, i could now adjust the timing and the check engine light appears. It idles very smoothly now! i did´nt do it with a timing light yet, but i will get this from a colleague on tuesdag.
But, there the check engine signal on when i dont have the TE1 and E1 bridged as well, but no fault codes.
And also, when i touch the throttle the car stops. This is maybe because i need to adjust the timing with a light?
Also there is comming very much dirt out from the exhaust, its some black dirt mixed with what looks like water. water in the fuel tank maybe? If it was coolant, would´nt it be red? And if it was fuel, would´nt it be smelling fuel?
I cleaned the spark plugs 3 times now, wich is according to the manual, not something i should do with platinum tipped plugs. Im gonna buy new ones tomorrow.
Now if i start the car i can let it run on idle OK, but if i stop the car iand try to start it 1 min after it won´t start. If i wait 30 minutes it starts up again...

When i changed the head gasket i did clean the butterflies, and i removed the throttle housing with the valves and cleaned these.

I ohmed the air intake sensor OK.

I think i got the vacuum hoses to the right places. at least i marked them when disasembly. I did find one bad hose today though wich i fixed. im going to replace all the vacuum hoses soon.

The high tension cords are ohmed ok.

Thanks, Espen!

EspenD
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Re: 3-sge Jumping when steady speeding.

Post by EspenD » 20/03/17 22:20

Short update in hope that someone will understand more than I do about this..

So i changed the plugs and adjusted the timing with a timing light, idles good when cold.
The warmer the engine gets the lower it idles. i had to adjust on the mixture screw a couple of times on the throttlehouse to make it idle OK so that i could try and warm the engine up once, in hope that there would be a fault code, but there was nothing. Still check engine light but no fault codes...
When i hold the throttle in 100% it reaches 1800rpm max. when i let go the engine will stop.
*When the engine stops, i have to turn the ignition off and on again for it to start, if not theres no sign of life...

*After the engine has been running and the engine is warm i might have to wait for say minimum 5 minutes for it to start again..,*

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