2.0lt. engine missing Options

[Tab914]

Hey guys! Hope someone out there can help me out. I'm having problems with my engine coughing ( missing ) and sputtering when accelerating and also on steady revs at about between 2000 and 3000 rpms. This causes the car to lose power and shutter. The problem is worst once car is warmed up. The car starts great without even having to step on the gas but idle sometimes becomes erratic. I adjusted the dwell, timming ( with strobe ) and idle ( idle as best i could ) but can't put my finger on the problem. I would appreciate any tips, info, or idea anyone might have. Cheers, Dominic.

p.s. I'm in the Canadian rockies, would elevation change specks car should be at??

[bondo]

Engine missing? Where'd you see it last? (IMG:style_emoticons/default/lol2.gif)

(sorry, couldn't help it)

[Tab914]

Hey Royce! I was expecting that one. (IMG:style_emoticons/default/biggrin.gif)

[bondo]

On a more serious note.. if it still has the original d-jet, maybe it's the cylinder head temp sensor? I think the Manifold pressure sensor is supposed to adjust for elevation changes.

[Tab914]

How would I test that sensor??

[bondo]

Everything you could possibly need is right here: pbanders' d-jet page

If I remember right, the sensor should be 2.5k or so ohms when cold, and under 100 ohms hot.

[Tab914]

Will check that page out right now and go from there. Thanks Royce. (IMG:style_emoticons/default/beerchug.gif)

[nebreitling]

mps automatically adjusts for elevation -- Jeff Bowlsby just taught me that yesterday...

check out the CHT and ALL of your electrical/ground connections.

check TPS.

i'd suspect ignition, as well.

[Tab914]

Hey Nathan! This might sound stupid but what is the CHT? Also can you tell me how the ignition might have something to do with this? Thanks Nathan.

[SLITS]

Hey Nathan! This might sound stupid but what is the CHT? Also can you tell me how the ignition might have something to do with this? Thanks Nathan.

I ain't Nathan, but if your high tension wires (in Canada, they are known as spark plug wires) are old, they can arc to ground or between each other. I used to wait until it go dark, fire the engine and rev it a couple of times to see if they were arcing. There is a better method with a VOM (volt-ohm meter).

In the cap, the spark can arc to ground. This is easily seen inside the cap as black fine lines that look somewhat like lightening bolts. Or the contacts can be so worn/corroded that the spark doesn't jump from the rotor.

Bad spark plugs

etc etc etc on ignition.

Other than that -

Bad tracks in the TPS (throttle position sensor)

Dying fuel pump - can't get up to operating pressure when warm

CHT = cylinder head temperature sensor - near #4 cylinder in a hole thru the tin - a bitch to get at. Otherwise
known as temp sensor #2

[Tab914]

Thanks Slits! The fuel pump is brand new, I checked the temp. sensor and it is showing the ohms reading. The plugs are good. I have the throttle position sensor in my hands right now. Took it off to check the contacts. Found some corosion and cleaned all of that off. What exactly do you mean by " bad tracks" ? Also is it possible to test the switch with a meter while it is out of the car? If so how? I will have another look at the plug wires and inside the cap. Might also use the fireworks method in the dark just for the hell of it.

[McMark]

Sounds like a TPS problem to me. Bad news, you can't test them reliably. [edited to remove moronic statement]

[SLITS]

The site on D-Jet will talk about the tracks in the TPS = over repeated cycles, they will wear, just like ignition points.

[Tab914]

I have to say it's got some good grooves on there. You guys just might be right. Anyone know where I can get one cheap??

[nebreitling]

Sounds like a TPS problem to me. Bad news, you can't test them reliably. Maybe with a machine to spin the distributor shaft and an oscilloscope to watch the pattern.

you talkn about the fi points, mark?

[nebreitling]

tab914, is this a new car that your bringing back to life? or did this problem recently develop?

in the case of the former, it may be difficult to track everything down that's wrong. if the car has sat for a while, then you could have a compound problem. be methodical, it will save you time and money in the long run.

anyway, if your tps is scored badly, you'll want a new one anyway. google the part number for the lowest price.

but before you dig into the FI, i'd make sure that your points, rotor, cap, wires etc. are good. check the timing if the car will run. then move on. fuel pressure, etc.

things like MPS and FI trigger points are harder to test for -- i save those for last.

[McMark]

Sorry I'm a moron. I think the TPS is bad. (edited previous post). Still no definitive way to test a TPS.

[Tab914]

Hey Nathan! This is a car I picked up last summer and have been working on since. This problem is new though. The car ran fine. Finally got the car certified and plated and now this. Will deal with this switch and move on to rechecking everything. I did unplug the switch to see if the problem would go away but it persisted even when the switch was unplugged. I read somewhere that if the switch was the problem, the coughing would not occur when switch was unplugged. Do you know if that is accurate?? Does this spawn any other ideas for anyone?

[nebreitling]

unplugging my TPS made my car run really rough, but i assume that any specific throttle enrichment issues would cease.

if the problem still manifests itself, i'd look elsewhere -- like the FI trigger points. does your gas mileage suck? running real rich? bogged down? -- or just a "flat spot"?

[Tab914]

Yeah gas milleage does seem high and car sometimes smells like it is runnig a little rich. When car is warmed up it really sputters and buck on acceleration. ( or lack of acceleration )