When I come to stop signs, red lights, etc. My oil pressure drops and my motor starts to studder (sounds/feels like its going to die, but bounces back, then drops down again, then goes back up). I haven't really noticed the RPMs bouncing like the oil pressure, but it idles at about 500RPM. What could be causing this problem?

 

If the car you are talking about is the one in your sig, then you have bigger problems if you are finding stop lights and street signs when driving it.


It would help if we had a better description of your vehicle and engine. Is it a carb or FI? Does it only happen when it is cold or all the time?

It sounds like your idle is set a little bit low, it should idle at 900RPM while in neutral, and 600RPM in gear with an auto. if it only happens when it is cold, there is nothing to worry about, just let it warm up and it'll be fine. When the RPMs get too low the oil pressure sending unit sometimes doesn't get enough imput to give an accurate reading. As a "live with the problem solution" I would just do a little bit of heal toe action while ocming to a stop... that is what I do to keep my carbed car form stalling when it hasn't had enough time to warm up. Just give it enough gas so it doesn't die, then let off and see if it idles right once you are completely stopped.

 

lol, The car in my sig is one we built for a good friend, and yes believe it or not it HAS seen stop lights (Some racer's cruise in Florida).


My engine is an L03 TBI w/ an automatic tranny. Oddly enough it only does this in drive and it seems like mainly when it is warmed up it does it.

 

Anyone?

 

i think if you're smart enough to built the car in your sig for a friend you ought to be able to figure out a driveability problem.

 

I help make them, not keep them running.

 

i would suspect a vaccum leak or a miss..

 

I'll check my vacuum lines, I know my cap is bad, could that be causing it?

 

My two bits are with ede.
You've been posting relentlessly for over a month, have disrespected some of the most senior members of the board (as well as the rest of the members) and won't follow any advice you are given.
You were told about three weeks ago to give your car a tune up, along with a list of items to change (including the cap) and you still have not changed the bloody cap.
You can't change spark plugs, but you are "...someone who is part owner of a world wide drag racing business..." and allege you helped build the car in your sig.
Umm... You can't build 'em if you don't know 'em... Strike that. You can't build 'em WELL if you don't know 'em.
On top of that you are "...A LOT better off than you will ever be..." (in reference to someone you obviously don't know and broadcast generally to insult all) yet can't afford to purchase the necessary components to give your car a tune up?
You then go on to lecture one of our most upstanding and knowledgeable moderators on BBS etiquette? You do this after the fact that he glossed over your previous slam of another member in the same thread? Are you daft boy or just dumb?


BTW:
1. It's shudder, not studder.
2. Oil pressure is usually relational to your rpm, figure it out.
3. If you are truly mentally challenged I apologize profusely in advance.

 

Allll Righty, then.....

As part of the check for vacuum leaks, don't overlook the PCV valve, power brake booster, and EGR valve. A leaking EGR is simply an internal vacuum leak. The low idle RPM sounds like it could be a vacuum leak, or other things. If the vacuum leak check doesn't reveal anything, take a close look at the throttle body, IAC air passages, and EGR valve and passages. If you haven't done so in a while, clean the throttle body, remove the IAC and disassemble/clean/lubricate it. Make sure the TPS voltage is within specs, even though your's is probably not adjustable on your '92.

 

And that ^ is why he is one of our most upstanding and knowledgeable moderators. What a jerk huh?

 

I'll be the bigger man here and ignore the ignorance, according to everyone's reaction to my behavior it is not okay to defend yourself or to react to an insult. Also compare a dragster motor to that of an everyday street car, let's think of how simplistic one is. I'll leave it at that.


I just replaced the PCV, so I know it is not that. Also just replaced the wires. If it was in the throttle body, wouldn't it do it in park or while driving, not just when in drive and stopped?

 

Fundamental troubleshooting abilities still apply.

air
fuel
spark

 

I had the same problem a long time ago when I still had the old enine in my car and it turned out to be the egr or at least I think so. Because I bought a cop car chip and had the egr taken out and I switched to a non egr intake (performer RPM) and my problem went away. Good Luck.

 

A simple thank you would have sufficed..

 

In a no-load condition, like in neutral, idle will tend to be higher since the engine requires less power to maintain RPM. If the IAC cannot provide more air once the engine has some load (in DRIVE) the RPM will drop, and the engine may have difficulty running. It's worth a look.

 

I'll go have a look at the intake right now, try cleaning it a little also. Somehow my gas mileage has gone to hell in a hand basket, may just be my imagination, or the fact that I drive 20-45 minutes in stop and go traffic everyday twice.

 

Bad gas mileage is another symptom I had. I bet its your egr valve.

 

hmm bad gas mileage low oil pressure im not a super mechanic or anything here but id be willing to say try a tune up ......lol

 

That kind of driving won't net you anything like "good" gas mileage no matter what you're driving - Except possibly a moped.

Since we don't have benefit of seeing/hearing/diagnosing the engine, we have to rely on you for feedback to make any kind of reasonable guess.

IROC is right about the possible EGR, or any other vacuum leak, internal or external. Check your hoses and potential vacuum leaks closely. Since you mentioned that the PCV valve is new, consider cleaning and reinstalling you old one as a test. I've had aftermarket PCV valves that were poorly calibrated for flow (which is critical on a speed/density setup) and caused me great angst until I replaced the aftermarket junk (Fram) with a factory replacement (AC/Delco) part.

However, you've already acknowledged that you have a "bad" distributor cap. Since you've identified that, the very first thing to do is replace it, and the rotor. When you remove the plug wires to transfer them to the new cap, inspect the boots and the entire length of wire for damage, melting, cuts, etcetera. Meter the wires from end to end for continuity. If they're good, continue to use them. If they're bad, replace the faulty ones. Don't overlook the coil wire.

While the distributor cap is off, inspect the connections at the HEI amplifier/switching module in the base of the distributor. Also look at the pickup coil and reluctor for signs of heating, excessive rust, and cracks. Since you have your meter out to check the plug wires, test the pickup coil winding resistance. It should be in the neighborhood of 850 ohms. Test the pickup coil to ground as well. You should read infinite resistance (no reading). If everything check out, finish up the new cap and rotor installation and consider that part of the system sound, so you can concentrate on looking elsewhere.

And the Devil is right, too. Slow down a bit, and don't be so defensive. The whole purpose of this board is to solve your problem, and others like them. We're not here just to pick on you, after all. That is left for other sites like www.Pick_On_Rebel_Til_Death.com, or www.Vader's_an_Idiot.org ...

None of these replies would be here if people weren't trying to help in some way, either with the car or the operator.

And yes, a bad distributor cap an cause or contribute to the type of problems you are describing.

 

Well, I took the vacuum line off my EGR, put my finger over the nipple ( I know it's not called that, but it's the best description) and it didn't stall, there wasn't even suction.

Also, my motor constantly makes a ticking noise, it's not very fast, but by no means slow, and it is in a definite pattern. What could this be?

 

Is this tick RPM-dependant, like does it speed up as RPM's increase? or is it constant throughout? If its RPM related, id look in and around the valvetrain (valve lash, pushrods, lifters, etc.) for causes. Exhaust leaks can tick, too.

If its constant, look elsewhere.

 

RPM related, I was thinking exhaust leak also.

 

Is it audibly coming from the engine bay?

 

there won't be vacuum from the egr. only vacuum to it from the line. apply vacuum with a pump to the egr and see what happens. it should run worse

 

Yup

 

That faint ticking could be crossfire at your "bad" distributor cap. Have you replaced it yet?

 

It will be replaced tomorrow. Like I said, I don't have the money right now, and my paycheck from this past monday got held back, but I'll have it tomorrow to go buy a cap and rotor.

 

Your oil pressure is low and fluctuating.

Your engine has begun to make ticking sounds.

You don't have the money and your check is on hold.

But wait, I have good news...


I just saved $120 on my insurance by switching to Geico.

 

now it's time to clean off the monitor

 

:hail:

 

I am have been having the same problem with my 89 TBI.
I had replaced the EGR...it still did it.
I had replaced the cap, rotor,and module....still did it.
I have just recently replaced the plug wires last night. I haven't driven it yet to see if the problem is fixed yet, though.
While I was under the car (changing #8 plug wire), I noticed that one of the manifold bolts had came loose. Might want to check to make sure all yours are tight too. Even a small exhaust leak can cause it to act like a missfire sometimes.
I think the ticking noise you are describing might be the sound of the injectors running.
Are you getting an SES (check engine) light at any time?
Before I replaced my EGR, I would get a light every once in a while when I was driving over 50mph consistant, for over 2 minutes. Scanned with my shop's scanner, it told me either EGR valve or the solenoid. Vacuum testing on the EGR showed that it was infact leaking down over time.
You mentioned that you replaced the wires, have you also changed the plugs too? If/when you do, remember to never trust that they are pre-gapped. always check the gap yourself.
305 = .035
Good Luck

 

hmmmm, involved in race business, knows all about race motors, and cant distinguish a ticking sound, or a needed tune up.?

 

im willing to bet if you put a good tune up on it and a quick check of your exhaust for leaks and fix any and all of em you probably will have solved your problem

 

And he is garrulous in his posts yet does not follow the advice given from the many threads, can not do fundamental troubleshooting on his own motor, in his possession, yet attempts to troubleshoot others' dilemmas via the internet, can't change his plugs, is a self proclaimed affluent person yet can not afford a $20 cap and rotor set, nor apparently a Haynes or Chilton manual, has alleged ownership in a worldwide racing organization yet talks about checks and employee discounts instead of disbursements and employees, and is VERY touchy about the word ******* whether directed at him or not, regardless if said in passing or in a joke.

Yet <i> we </i> are the ignorant ones.


Let me clear up my previous post. I believe you owed five7kid, Vader, and especially RB83L69 an apology for your asinine behavior in
this post . Learn how to take a joke, it will serve you well beyond any monies you plan on, apparently, inheriting.

You apparently don't get the hint. Instead of being so ridiculously defensive, listen to the damn advice given to you by the senior members, they are usually right. And PLEASE, until you develop some good diagnostic skills, stop trying to help people by randomly guessing or repeating information, it wastes people's valuable time. And you may want to hold off on posting a derivative of a previous post until you have followed the advice in that post.

BTW:
Main Entry: ig·no·rant
Pronunciation: 'ig-n(&-)r&nt
Function: adjective
1 a : destitute of knowledge or education <an ignorant society>; also : lacking knowledge or comprehension of the thing specified <parents ignorant of modern mathematics> b : resulting from or showing lack of knowledge or intelligence <ignorant errors>
2 : UNAWARE, UNINFORMED
- ig·no·rant·ly adverb
- ig·no·rant·ness noun
synonyms IGNORANT, ILLITERATE, UNLETTERED, UNTUTORED, UNLEARNED mean not having knowledge. IGNORANT may imply a general condition or it may apply to lack of knowledge or awareness of a particular thing <an ignorant fool> <ignorant of nuclear physics>. ILLITERATE applies to either an absolute or a relative inability to read and write <much of the population is still illiterate>. UNLETTERED implies ignorance of the knowledge gained by reading <an allusion meaningless to the unlettered>. UNTUTORED may imply lack of schooling in the arts and ways of civilization <strange monuments built by an untutored people>. UNLEARNED suggests ignorance of advanced subjects <poetry not for academics but for the unlearned masses>.

Just some help in furthering an education, hopefully.

 

Well, we get all kinds here. Seems like every day if you look around on these boards you can find a couple of these. Makes me wish we could search for easier. That way when i need a good laugh I can search and read stuff like:



now i am really confused. What is simple, the drag engine? I dont know about that. Or is it the regular car engine? Either way you ought to be able to fix it. That or pay to have it fixed with your worldwide drag racing business.

 

Hi all, i'm new to all this, i got an '86 iroc 305 in the uk, i had the juddering problem with mine, i umplugged the temp sensor and it runs fine, the computer couldn't determine whether my car was running too hot or too cold, :hail: