Not for the first time, I'm trying to diagnose a high idle problem. But I'm not an expert engineer, so I'd welcome some step-by-step advice.
I have a 1988 Fiero Formula (2.8V6). The catalyst was removed some ten years ago, and replaced by a standard muffler pipe.
A couple of years ago, the engine used to idle when cold at between 1500 and 1800 rpm (sometimes higher). I discovered that the EGR tube was leaky/corroded. I replaced it with one from Rodney Dickman, and that seemed to improve matters slightly.
I haven't used the car over the winter, but it now seems to be suffering from 'high idle' again. The other possible clue is that the engine has always run very cool (at least according to the temp gauge, where it barely reaches the second marker-line on the dial). When stuck in traffic or idling in Park for a long period, it does warm up closer to the midway point on the gauge, and when it is that hot, the idle speed drops to around 850-900 rpm.
The latest annual roadworthiness check indicates that the emissions are close to, if not over, the limit, so something needs to be done!
To my simple mind, the evidence suggests that the engine is running "rich" - as if there was too much choke (except that there is no manual choke). I don't have the expertise to run a WinALDL scan. What other checks can I do, and in what order, to try and identify the cause of the high idle/running rich/high emissions problem?
[This message has been edited by br1anstorm (edited 04-18-2018).]
Probably vacuum leaks. At my repair shop we use a “smoke” machine and that allows us to find all sorts of broken lines, torn gaskets, etc. We even use It to find exhaust leaks in a similar fashion. My ‘88 had all kinds of air leaks in the intake and exhaust system, it would fail the emissions like crazy. Fixing all the leaks cured nearly all of my issues...
[This message has been edited by Crasian (edited 04-18-2018).]
It doesn't take much "expertise" to read the values for things such as Manifold Air Temp, Coolant Temp, etc. Just using the most basic aspects of WinALDL can be most helpful when troubleshooting.
[This message has been edited by Patrick (edited 05-03-2018).]
It doesn't take much "expertise" to read the values for things such as Intake Air Temp, Coolant Temp, etc. Just using the most basic aspects of WinALDL can be most helpful when troubleshooting.
Hmmm, we'll see. I have the necessary cable, and the WinALDL software on an old laptop. But it doesn't exactly look like "Plug 'n' Play" . It's the setting-up that looks like witchcraft to me.
Hmmm, we'll see. I have the necessary cable, and the WinALDL software on an old laptop. But it doesn't exactly look like "Plug 'n' Play" . It's the setting-up that looks like witchcraft to me.
You've even got the cable! Well damn... it's not that bad!
Is your cable USB or serial? The biggest nuisance (sometimes) is simply configuring the laptop to the correct COM port.
You've even got the cable! Well damn... it's not that bad!
Is your cable USB or serial? The biggest nuisance (sometimes) is simply configuring the laptop to the correct COM port.
Ah, when it comes to spare parts and bits 'n' pieces (I have other cars besides the Fiero) I collect and hoard anything that might come in useful or might go out of production. You should see the roof-space in my garage.... everything from spare windscreen to headlight motors.
So yes, I got a cable (from Dodgerunner IIRC) a while back, reckoning that sometime I would have to get around to using it. Has a serial connector, which I hope will be OK as I have at least a couple of old laptops (one Win98, one XP) which have the right sockets.
Hence my search for advice... but many forum posts seem to consist of geeky esoteric dialogue between people who already know what WinALDL is and what it does and what the readings mean! I am still at the stage of trying to figure out (a) the physical connections, the ports, and what plugs in where, which seems pretty straightforward (provided I don't have to mess around with extra resistors...); (b) the actual setting up of the WinALDL program, ie what parameters or engine codes have to be set, or is it just a matter of using the default settings? and (c) the big banana: understanding the results, whether a row of numbers or a line on a graph. Until you know what the normal readings should be, you have no chance of spotting any discrepancies or knowing what caused them or how serious they might be.
Maybe this weekend will be my trial run with this unfamiliar technology......
As long as your laptop has a serial port, the serial cable you have is actually preferred over the USB version. Seems to be easier to configure the COM port etc.
Have you got ALDLView? If not, click on that link to read about and download it.
[This message has been edited by Patrick (edited 04-19-2018).]
Thanks Patrick - have just gone to look at ALDLView and have downloaded and installed it. Looks as if it will help to make sense of whatever numbers emerge from the logging.
Okay - for Patrick and other readers - I now need your help!
A quick recap. My 88 Formula (2.8 V6) seemed to have a high idle at least while cold (it runs cool, but when really warmed up the idle speed drops to the normal 950-ish). Its catalyst was removed some years ago. It is showing no fault codes on the SES light. But it is perilously close to failing the UK emissions test. On a "non-cat" meter test, the CO emissions are at, maybe above, the limit.
So I have finally got round to trying out WinALDL. The good news is that it all seemed to connect up OK (Dodgerunner's cable and my old Windows XP computer). I ran the engine on Idle in Park for a while, then took a very short drive around the block, just to see if the program produced some readings. It did.
Now the bad news (sort-of). I haven't the foggiest idea what the numbers mean, nor can I interpret the ALDLView graphs. I still have no idea whether my engine is running correctly or not, nor why the CO emissions are so high.
Hence my help request. I took advice from a YouTube video and set WinALDL to log the BLM and INT readings (and I also did the O2 table). I looked at the other displays while WinALDL was running and the car stationary in Park, and saw nothing that looked weird. In "Flag Data" it intermittently showed a tick for "DRP occurred" (what's that?), a tick appeared to show IAC motor and coil active, and I once saw a "Low RPM hysteresis" tick appear then vanish. Otherwise nothing. No error codes on that page of the display. The Sensor Codes page populated with numbers, but I have no idea whether they were all "normal". I did notice that the screen RPMs were lower than the tach (presume the tach is not terribly precise).
So..... I now have a WinALDL LOG file, and BLM, INT and O2 tables, all as .txt files. I can open them as graphs in ALDL view. But I can't interpret them.
Can I upload the .txt files somehow (or send them separately by email to someone?) to get an analysis from someone who understands? Or a bit more tricky - do I have to try to take screenshots of the tables or graphs and insert them as images in a forum post?
Advice - either by reply to this, or by PM - would be welcome......
Can I upload the .txt files somehow (or send them separately by email to someone?) to get an analysis from someone who understands? Or a bit more tricky - do I have to try to take screenshots of the tables or graphs and insert them as images in a forum post?
I'm just going out the door, but here's something quick...
The first thing I like to check is that both the Manifold Air Temperature and Coolant Temperature sensors are working properly. After the car has sat all night, see what the readings are. You can plot multiple readings on the graph at once, and ALDLView will also save GIF's of what you're looking at.
Here's an old reading I just randomly grabbed of my Formula. Notice how when the engine starts, the two temperature readings are very close to each other.
Thanks Patrick. Have discovered how to display two (or more) sets of data on the ALDLView graph, and how to save a .gif.
But how do I post up or insert an image within this post like you did in yours?
Do I first have to upload it into photobucket or a similar online website so that it has a URL?
Sorry for dim question, but it's not obvious how this is done......
If all such images have to be posted up on to a third-party website first, can you just suggest which particular data (or combinations of data) I should snapshot. I'll then post up a series of .gifs of my WinALDL readings for people to look at and comment on.
But how do I post up or insert an image within this post like you did in yours?
You've been registered with PFF for ten years.. and you're unaware of PIP?
If you're running a Windows computer, use PIP to post images here. Max width - 1024 pixels. Max file size - 300 kb.
In regards to what else for you to check with WinALDL, someone else will need to step up and offer you some advice. I've never advanced beyond the most basic tasks with it.
I do have a question though... What degree thermostat are you running? Your coolant temperature takes a heckuva dive after initially reaching 197º or thereabouts. That'll certainly affect your emissions. Compare your coolant temps to mine. Spend a couple extra dollars and buy a superior 195º thermostat - Stant SuperStat 45819.
[This message has been edited by Patrick (edited 05-03-2018).]
Yikes! You learn something new every day. I confess..... I'd never heard of PIP. Never thought to go looking. I did check the forum FAQs which said that files couldn't be uploaded, but had to link to a URL. I think the last time I sought to post a photo into this forum was several years back, when I derusted and painted the sills (=rockers?) and put a bunch of pics on Photobucket. I'd done something similar on the NAXJA Jeep forum after some work on my Cherokee.
But there's another catch. I now use Linux and have abandoned Mr Bill Gates' enterprise completely. I do have a really old laptop with XP (now deployed in the car with WinALDL). But all my current business is done on a Linux system. Another, better, safer, more reliable world altogether. I fear PIP may not play with Linux (and I hesitate to try.....). But that is another story, and I digress.
Back to the task at hand. To answer your latest question - I admit I don't know what thermostat I'm running, but it will be the original: I haven't changed it in all the 25 years I've owned the car. The engine has always run pretty cool at least as shown by the gauge on the dash. I thought this a good thing (I have had the opposite problem, overheating, both in my other mid-engined car, and also in the Jeep), and I have always worried that the mid-engine layout risked allowing the engine to get very hot while the radiator at the front stayed cool.....
But there is a specific explanation for the "dive" on the graph I posted. The temp rises gradually but steadily if the car sits idling or in Park (as it did for the first 15 mins or so of my WinALDL test). Then if you turn on the a/c, the electric fan kicks in and the temp drops back rapidly especially if you rev the engine a bit. I reckon that - and/or the fact that I drove off around the block - is the explanation for the "dive". In normal running I'd say the temp rarely goes above maybe 170-ish except when stuck in traffic.
It would be interesting if a change of 'stat were to make a major difference to the emissions. I'm game to try it (not sure I can get the Stant brand over here, but I'll search). Meanwhile if there is anyone other than you and me following this thread, I'd be happy to see other comments either on posting up more WinALDL results, or indeed on the thermostat angle.
I admit I don't know what thermostat I'm running, but it will be the original: I haven't changed it in all the 25 years I've owned the car. The engine has always run pretty cool at least as shown by the gauge on the dash. I thought this a good thing (I have had the opposite problem, overheating, both in my other mid-engined car, and also in the Jeep), and I have always worried that the mid-engine layout risked allowing the engine to get very hot while the radiator at the front stayed cool.....
In normal running I'd say the temp rarely goes above maybe 170-ish except when stuck in traffic.
It would be interesting if a change of 'stat were to make a major difference to the emissions. I'm game to try it (not sure I can get the Stant brand over here, but I'll search).
It's no wonder you've got emission problems! Your engine needs to be running at the correct temperature. The lower than normal coolant temp might also be contributing to the higher than normal idle speed.
Have a look Here as to why the Stant SuperStat is highly recommended. Maybe someone in the States could ship one to you in the UK. (It would be cheaper to buy and to ship from the States as opposed to from Canada.)
[This message has been edited by Patrick (edited 05-03-2018).]
It would be ironic if the explanation for high emission and high idle was just that the engine was running too cool. A simple explanation when I was thinking the ALDL data would reveal something complicated.
I'd still like to have someone cast an expert eye over all my WinALDL data now that I have finally managed to run the program! So I'm still hoping for someone to step up and tell me what other readings to post up as images.
Meanwhile I think I just have to go ahead and replace the thermostat with that Stant 45819 'stat. Sure enough, Stant products are totally unavailable in the UK so I will have to find a way of sourcing one from the US. I'm up against the usual problem (mentioned on this forum before). Suppliers like Rock Auto who are willing to despatch orders internationally charge a fortune for shipping. It's worse on small items, because the shipping costs more than the actual item. And there's a double whammy: the higher the shipping cost, the more likely that I get hit at this end for UK customs and import dues because they charge duty on the total value including shipping!
So a $9 part can end up costing a total of over $40 if there is $20-ish shipping and the equivalent of $10-12 in customs and import duty, which is ludicrous.
But enough of moaning. I have discovered that Rodney Dickman offers the Stant 45819 on his website so I've emailed him to ask whether he can send one over by post for a sensible price. Otherwise if any other US-resident forum regular is willing to volunteer to send me a the right 'stat, I'll gladly reimburse the cost via PayPal... Any such offers of assistance by PM, please, and I'll provide address details etc directly....
Well damn... it's not that bad!
